Even ROCm on some distros isn’t that bad. On my 7900 XTX (admittedly an officially supported card, your mileage may vary on unofficial cards) on Fedora it was just a case of doing sudo dnf install rocm-* and everything installed (might be some extra packages you need after for specific apps, but you know if you need them). On openSUSE though, it was a total pain.

Works fine for me in KDE when icons are also set to Breeze Dark. Page goes dark, icons go light, toolbar goes dark.

I would suggest holding off on buying an ARM laptop specifically for Linux at the moment (maybe not too long from now though). Although there is an increasing amount of support, it’s still not fully there, and there is most likely going to be quirks here or there that can throw some issues you would rather not deal with on a daily driver machine (e.g. having to extract firmware from the Windows partition in order to get some features working for the Snapdragon devices). Probably your best combination of power efficiency and performance on x86 at the moment will be something like the Ryzen AI 300 series CPUs. If you like ThinkPads, I would suggest the Ryzen version of the T14s Gen 6, which is essentially the same as the ARM version bar the CPU. I’ve been using a P14s (very similar to T14s just with some tweaks as it’s marketed for mobile workstation users) Gen 5 and even with the lower capacity 39.3Wh battery (compared to the 57Wh battery you can get on a Gen 6) I’ve easily been able to get 6 or 8 hours in the balanced power profile with ~70% brightness on Fedora, so probably the T14s Gen 6 can do 10 or 12 hours on a charge.

Without a doubt. Very good MS Office compatibility now, alongside a user interface that gets me to what I need and is heavily customisable, and very well done integration with Zotero (the best thing ever for citations) through an extension comes together to being by far my most preferred office suite even when I have to use Windows. In addition, Draw has saved me at least a few times when I’ve had to deal with some PDFs that other software finds difficult to work with.

Same on AMD as well. vaapi acceleration, after installing the appropriate packages, works nearly flawlessly on all brands of GPU I have tried.

Strawberry for music transfer and GPodder for podcasts works perfectly on my iPod Photo, although both of them do have slightly clunky interfaces that may take a bit to get used to. Rhythmbox also works great, although I haven’t been able to get it working on my current Arch setup yet.

If you aren’t trying to run anything too crazy (like AMD HIP compute, HDR, really bleeding edge hardware) I would probably recommend giving openSUSE Tumbleweed, Fedora (only the regular GNOME version, for some reason KDE spin was buggy in my experience), and Pop OS a test drive off live USB drives. Each has their own merits, so it’s worth trying all of them. In terms of NVIDIA support, I personally do not have much experience with NVIDIA cards, but when I was helping a friend format an iPod Fedora booted off a live USB on an RTX 4050 laptop with little fuss, and if you install it gives options for installing the full proprietary NVIDIA drivers. I know there is also an NVIDIA installer option in YaST’s software manager for openSUSE, and Pop even has an ISO with the drivers baked right in for full compatibility. However, your mileage may vary, although I have heard the whole NVIDIA situation is pretty good right now as long as you have the proprietary drivers installed.

openSUSE Leap - YaST is the greatest thing since sliced bread, and works great on command line over SSH. Yes, sometimes installing some software is difficult, but generally most stuff you would want is there and a lot of stuff runs on Docker anyway now. Very stable too, have had nearly zero issues.

Yup, was using Spectacle, behaviour was similar to your description. I guess maybe the HDR highlights just got more blown out on higher brightness displays?