[Magisk] pndwal:
Sorry, but apparently It did not... It had the block just as John said is expected, but ramdisk parts were missing as @martyfender said:

... Only after patching does ramdisk folder contain init etc.

Simply, the only ramdisk factory supplied in /boot on Legacy SAR devices are recovery type ramdisks in A/B types (ie. devices launched with A7: Pixel, A8, Pixel 2 + OnePlus 6, & A9: all) designed to boot recovery (Hardware/bootloader is configured to use only a recovery ramdisk, BOARD_USES_RECOVERY_AS_BOOT: true) but moved from /recovery partition to /boot in Legacy SAR while boot ramdisk has been removed... This recovery ramdisk is not used to boot system with these devices in factory configuration (kernel directly boots system), but Magisk can use it where it exists (A/B type) to boot system with Magisk root... This means the original one stage Legacy SAR becomes a form of 2SI (2 stage init) with Magisk installed. See:

https://source.android.com/docs/core/architecture/partitions/ramdisk-partitions#ab-boot-img

Of course on A-only Legacy SAR devices (ie. devices launched with A9: all) Magisk installs its own ramdisk when patching /boot just in case bootloader has support for ramdisk in /boot... It is reasonably expected that this configuration will not be usable but inexplicably some A-only Legacy SAR devices (Xiaomi and other) have bootloader support. (Likely bootloaders are not created form scratch by some OEM's, but copied from older devices and altered enough to work so unused functionality may remain.) Where this is usable, the original Legacy SAR has become a form of 2SI with Magisk installed too.

In 2SI ramdisk SAR A/B devices (ie. devices launched with A10+: all, A9: Pixel 3, 3a; possibly the only Legacy SAR devices to receive a 'retrofit' for 2SI on updating to A10), recovery ramdisk remains (with the exception below*) but is now hijacked to boot system also from factory... Hardware/bootloader is configured to use only the recovery ramdisk in /boot, and now both the recovery boot and system boot processes are designated "BOARD_USES_RECOVERY_AS_BOOT" by Google. See 'Ramdisk(Android 10 and 11)' column in chart from Android doc linked above. Magisk is actually using this same process (ie hijacking the recovery ramdisk) in all modern A/B devices.

Modern A-only 2SI devices (ie. devices launched with A10+: all, A8 and under: Any running A10+; Nb Legacy ramdisk devices automatically update to 2SI ramdisk SAR on updating to A10+ whereas Legacy SAR devices are 'stuck' as L-SAR without a 'retrofit') and devices that have hybrid a/b recovery partitions* (eg OnePlus 7T, 8, 8T, more?) have normal boot ramdisk restored (only used for system booting) so Magisk is able to simply use this. (BOARD_USES_RECOVERY_AS_BOOT: false) See:

https://source.android.com/docs/core/architecture/partitions/ramdisk-partitions#non-ab-boot-img

So Magisk is actually running in a recovery type ramdisk located in /boot partition in most A/B SAR/2SI devices... Notice the 'Ramdisk in boot' column in John's chart:

Nb. Hybrid can be recovery or boot type ramdisk depending on existence of /recovery partition.

https://topjohnwu.github.io/Magisk/boot.html#piecing-things-together

Here you go, you do it. 😜 (Attached A10 stock MIUI boot.img for Redmi Note 8T that was still on device.)

Hope this clarifies things... or not. 🙃 PW