[Nintendo Switch News, Guides, Discussion , Develop] Arbelzapf:
I was able to get some logs concerning my broken Wifi. Below is a logcat of me tapping on the wifi icon in the notification dropdown. There's some errors and I hope it helps getting to the bottom of the problem.

=u:r:magisk_client:s0:c84,c256,c512,c768 tcontext=u:r:hal_graphics_allocator_default:s0 tclass=fd permissive=1 app=com.android.terminal
02-08 20:40:39.375 6777 6777 I su : type=1400 audit(0.0:714): avc: denied { read } for name="audio.primary.tegra.so" dev="mmcblk0p3" ino=536 scontext=u:r:magisk_client:s0:c84,c256,c512,c768 tcontext=u:object_r:vendor_file:s0 tclass=file permissive=1 app=com.android.terminal
02-08 20:40:39.375 6777 6777 I su : type=1400 audit(0.0:715): avc: denied { getattr } for path="/vendor/lib/hw/audio.primary.tegra.so" dev="mmcblk0p3" ino=536 scontext=u:r:magisk_client:s0:c84,c256,c512,c768 tcontext=u:object_r:vendor_file:s0 tclass=file permissive=1 app=com.android.terminal
02-08 20:40:39.375 6777 6777 I su : type=1400 audit(0.0:716): avc: denied { read } for name="bin" dev="mmcblk0p3" ino=26 scontext=u:r:magisk_client:s0:c84,c256,c512,c768 tcontext=u:object_r:vendor_file:s0 tclass=dir permissive=1 app=com.android.terminal
02-08 20:40:39.727 6781 6781 D AndroidRuntime: >>>>>> START com.android.internal.os.RuntimeInit uid 0 <<<<<<
02-08 20:40:39.733 6781 6781 I AndroidRuntime: Using default boot image
02-08 20:40:39.734 6781 6781 I AndroidRuntime: Leaving lock profiling enabled
02-08 20:40:39.739 6781 6781 I /system/bin/app_process: Core platform API reporting enabled, enforcing=false
02-08 20:40:39.888 6781 6781 D ICU : Time zone APEX file found: /apex/com.android.tzdata/etc/icu/icu_tzdata.dat
02-08 20:40:39.906 6781 6781 I /system/bin/app_process: The ClassLoaderContext is a special shared library.
02-08 20:40:39.930 6781 6781 W /system/bin/app_process: JNI RegisterNativeMethods: attempt to register 0 native methods for android.media.AudioAttributes
02-08 20:40:39.938 6781 6781 D AndroidRuntime: Calling main entry com.android.commands.content.Content
02-08 20:40:39.957 6781 6781 D AndroidRuntime: Shutting down VM
02-08 20:40:39.967 6574 6574 I RenderThread: type=1400 audit(0.0:717): avc: denied { call } for scontext=u:r:untrusted_app_27:s0:c129,c256,c512,c768 tcontext=u:r:hal_cplservice_default:s0 tclass=binder permissive=1 app=com.topjohnwu.magisk
02-08 20:40:39.971 6574 6574 I RenderThread: type=1400 audit(0.0:718): avc: denied { call } for scontext=u:r:untrusted_app_27:s0:c129,c256,c512,c768 tcontext=u:r:hal_cplservice_default:s0 tclass=binder permissive=1 app=com.topjohnwu.magisk
02-08 20:40:41.115 3376 3376 I InputReader: type=1400 audit(0.0:719): avc: denied { call } for scontext=u:r:system_server:s0 tcontext=u:r:init:s0 tclass=binder permissive=1
02-08 20:40:41.972 3376 3911 W NotificationService: Toast already killed. pkg=com.topjohnwu.magisk callback=android.app.ITransientNotification$Stub$Proxy@f6bb064
02-08 20:40:43.435 3149 3149 I storaged: type=1400 audit(0.0:720): avc: denied { call } for scontext=u:r:storaged:s0 tcontext=u:r:init:s0 tclass=binder permissive=1
02-08 20:40:43.463 3376 3398 W WindowManager: Unable to start animation, surface is null or no children.
02-08 20:40:52.965 3376 3376 W WindowManager: removeWindowToken: Attempted to remove non-existing token: android.os.Binder@3f976a3
02-08 20:41:00.002 3586 3586 D KeyguardClockSwitch: Updating clock: 20:41
02-08 20:41:08.115 3376 3412 E LightsService: Light requested not available on this device. 2
02-08 20:41:08.117 3376 3470 E LightsService: Light requested not available on this device. 2
02-08 20:41:46.319 3586 3586 D StatusBar: disable<e i a s b h r c s > disable2<q i n >
02-08 20:41:46.363 3519 3538 D RSMouse : mFeatureEnabled=true mPackageEnabled=true
02-08 20:41:48.149 3376 4233 I WifiService: setWifiEnabled package=com.android.systemui uid=10097 enable=true
02-08 20:41:48.149 3376 3485 D WifiController: StaEnabledState.enter()
02-08 20:41:48.149 3376 3486 D WifiActiveModeWarden: received a message in WifiDisabledState: { when=0 what=0 target=com.android.internal.util.StateMachine$SmHandler }
02-08 20:41:48.149 3376 3486 D WifiActiveModeWarden: Switching from WifiDisabledState to ClientMode
02-08 20:41:48.149 3376 3486 D WifiActiveModeWarden: Entering ClientModeActiveState
02-08 20:41:48.150 3376 3486 D WifiClientModeManager: entering IdleState
02-08 20:41:48.150 3376 3486 D WifiActiveModeWarden: State changed from client mode. state = 2
02-08 20:41:48.151 3376 3376 D WifiP2pService: Wifi enabled=false, P2P Interface availability=true
02-08 20:41:48.151 3376 3486 I WifiVendorHal: Vendor Hal started successfully
02-08 20:41:48.153 3376 3486 I SupplicantStaIfaceHal: Starting supplicant using HIDL
02-08 20:41:48.154 3376 3487 I WifiP2pNative: Registering for interface available listener
02-08 20:41:48.156 3376 3486 I android_os_HwBinder: HwBinder: Starting thread pool for getting: android.hardware.wifi.supplicant@1.0::ISupplicant/default
02-08 20:41:48.156 3376 3486 E SupplicantStaIfaceHal: Death handler already present
02-08 20:41:48.161 3068 3068 E android.hardware.wifi@1.0-service: Failed to open wlan fw path param: No such file or directory
02-08 20:41:48.155 3068 3068 I wifi@1.0-servic: type=1400 audit(0.0:721): avc: denied { read } for name="fw_path" dev="mmcblk0p10" ino=784924 scontext=u:r:hal_wifi_default:s0 tcontext=u:object_r:wifi_vendor_data_file:s0 tclass=lnk_file permissive=1
02-08 20:41:48.161 3068 3068 E android.hardware.wifi@1.0-service: Failed to change firmware mode
02-08 20:41:48.161 3376 3486 D HalDevMgr: updateRttController: no one is interested in RTT controllers
02-08 20:41:48.161 3376 3486 E HalDevMgr: executeChipReconfiguration: configureChip error: 9 ()
02-08 20:41:48.161 3376 3486 E WifiVendorHal: Failed to create STA iface
02-08 20:41:48.161 3376 3486 E WifiNative: Failed to create STA iface in vendor HAL
02-08 20:41:48.161 3376 3486 E WifiClientModeManager: Failed to create ClientInterface. Sit in Idle
02-08 20:41:48.161 3376 3486 D WifiActiveModeWarden: State changed from client mode. state = 4
02-08 20:41:48.161 3376 3486 D WifiClientModeManager: expected stop, not triggering callbacks: newState = 1
02-08 20:41:48.161 3376 3486 E WifiNative: Could not get Iface object for interface null
02-08 20:41:48.162 3376 3376 D WifiP2pService: Wifi enabled=false, P2P Interface availability=true
02-08 20:41:48.162 3376 3486 D WifiActiveModeWarden: ClientMode failed, return to WifiDisabledState.
02-08 20:41:48.162 3376 3486 D WifiController: ClientMode unexpected failure: state unknown
02-08 20:41:48.162 3376 3486 D WifiClientModeManager: currentstate: IdleState
02-08 20:41:48.162 3376 3486 D WifiScanRequestProxy: Sending scan available broadcast: false
02-08 20:41:48.162 3376 3489 I WifiScanningService: wifi driver unloaded
02-08 20:41:48.163 3376 3486 I WifiScanRequestProxy: Scanning is disabled
02-08 20:41:48.164 3376 3409 D KernelCpuUidUserSysTimeReader: Removing uids 1037-1037
02-08 20:41:48.165 3376 3486 D WifiActiveModeWarden: Entering WifiDisabledState
02-08 20:41:48.166 3376 3486 D WifiActiveModeWarden: received a message in WifiDisabledState: { when=-3ms what=3 target=com.android.internal.util.StateMachine$SmHandler }
02-08 20:41:48.166 3376 3486 D WifiActiveModeWarden: Switching from WifiDisabledState to WifiDisabled
02-08 20:41:48.166 3376 3486 D WifiActiveModeWarden: Entering WifiDisabledState
02-08 20:41:48.166 3376 3486 E WifiNative: Could not get Iface object for interface null
02-08 20:41:48.169 4206 4782 W Settings: Setting airplane_mode_on has moved from android.provider.Settings.System to android.provider.Settings.Global, returning read-only value.
02-08 20:41:49.891 3069 3069 I joycond : type=1400 audit(0.0:722): avc: denied { read } for scontext=u:r:init:s0 tcontext=u:r:init:s0 tclass=netlink_kobject_uevent_socket permissive=1

EDIT:

I also grabbed a dmesg which I have uploaded to my server since it's too large to attach here

Grepping for "wifi"/"wlan" yields a whole lot of errors, for example:

service "vendor.wifiloader" exited with status 255

Naturally, wifi works just fine in Horizon, just in case you suspect faulty hardware