[General Questions and Answers] dankcuddlybear:
I want to buy a phone that's future proof and, after the manufacturer stops releasing software updates, supported for a long time with custom ROMs. So my best choice is obviously a popular 5G flagship phone. It needs to have a good camera (4K 60FPS, I make lots of videos and I want them to look absolutely stunning), a Snapdragon (NOT Mediatek) chipset, and a micro SD card slot*. Ideally it should be waterproof (I'm not too worried about getting it wet, except it rains a lot in the UK) and robust**, with a HDR display***.

Anyway, I'm considering these phones. I'd like to spend as little as possible. I haven't decided on one yet but my main concern is software support (official+unofficial). Even if I can't decide, someone else may find this list useful if they're unsure about what phone they want. The prices may not be accurate, but I looked for the best deals I could find from fairly reputable sites. None of these phones have Android 11 at the time of writing, but their manufacturer plans to release an update eventually, and some of them probably have an Android 11 custom ROM available for them already.

Sony Xperia 5 II (£800.00) - it has all the features I want, and includes a lovely 120Hz HDR BT.2020 OLED display, but it's very expensive. It has an IP68 water resistance rating.

Sony Xperia 1 III - it hasn't been released yet, and there's not much information on it, but it sports a Snapdradon 888 Chipset and features wireless charging (which I don't really need but it's still a nice option). It has an IP68 water resistance rating.

Asus Zenfone 7/Zenfone 7 Pro (£450) - the main camera and selfie camera are essentially the same, which does away with the pinhole/notch selfie camera design. Some people might be scared of breaking the motorized flip-up camera. You can record videos in 4K 120FPS or 8K 30FPS (although I don't see much point in recording 8K video unless you were making a movie perhaps). It has a smooth 90Hz HDR10+ super AMOLED display. It's not waterproof unfortunately, and there's no headphone jack (although I have a USB headset and bluetooth earbuds so I don't really use it much anyway). It's not yet available in the USA (although that might've changed by now).

LG V60 ThinQ 5G (£400.00) - this phone also has an 8K camera (again, quite pointless) and wireless charging. It also comes with a secondary display attatchment, which I don't see myself ever using. It has a 60Hz P-OLED display, same as the Google Pixel 2 XL which was prone to burn-in. It has an IP68 water resistance rating.

Nokia 8.3 5G (£300.00) - this phone has the least powerful chipset out of all phones in this list - a Snapdragon 765G, but I think it's still good enough. It claims to support the most 5G bands out of all phones, making it great for roaming. It has a 60Hz non-HDR IPS LCD display, and has no water resistance. The cheapest out of all phones in this list.

* I don't understand why so many manufacturers are getting rid of it. Sure it's slow compared to today's UFS internal storage but I like having the option to expand my storage for cheap. I like having all my photos, videos, music, APKs and other installation files on a removable card for convinience and in case my phone gets broken and I can't recover data from it. I would buy the Google Pixel 5 in an instant if only it had a micro SD card slot.

** Most phones just don't use screws or clips any more, they use adhesive. A stupid design choice IMO. The back plate is glued on in most phones, which I don't mind that much (at least a protective case will keep it on if the adhesive breaks down). But in some (like the Sony Xperia XZ1 compact) the screen is glued on instead. I bought mine used for £100 (1/5th of it's original price) and the screen kept popping off until I was able to fix it. Just imagine if I dropped it one day and the screen goes flying, ripping off the motherboard socket with it. Not good.

*** I have a sony Xperia XZ1 compact with a Triluminos display and it looks magnificent. There's no way I'm going back to ugly SDR displays. I use the camera a lot so I want to make sure my videos look good.