NVIDIA has apparently open-sourced the kernel drivers for their most recent couple generations of graphics cards. That's great! But they have a hell of a lot of catching up to do. Their kernel drivers aren't in the mainline Linux kernel. Their userspace drivers are proprietary, whereas AMD's are open-source. AMD's kernel drivers are built into Linux and their userspace drivers are built into Mesa.
That history of greater compatibility matters in its own right: all of the developers of Linux desktop environments, window managers, and compositors have been running AMD or Intel GPUs almost exclusively for many years.
If "voting with your wallet" means anything to you, or you want things to "just work", AMD is the clear choice and it's not even close.
If you already have NVIDIA hardware, by all means, go ahead. It's doable. But AMD is a way more rational choice on Linux for most users.
Any modern distro running NVidia or AMD should be fine. I've done both. I didn't have to do anything for the NVIDIA 3000 or NVIDIA 4000 series cards but select the nvidia driver. AMD otoh is built into kernel now.
Comparatively the leading alternative was a dumpster fire of a broken mess for the longest time on Linux. All through the 2000s, ATi provided a binary blob driver known as fglrx which some people joked was a half-baked codebase from somemthing that started on HP-UX, passable enough for running sales demos and then was thrown at an intern to port it to Linux. If you went with ATi and tried to do much with foss opengl programs, you could expect daily or weekly kernel panics and performance that was <50% of that of the windows driver for an identical build. The solution was always to buy nvidia if you wanted stability.
Nothing has really changed for Nvidia on Linux, it still continues to perform adequetly. Plenty of people, including myself have used the binary blob for games and other 3D software with wine through the late 2000s, 2010s and proton in the 2020s without much comment because it works fine. The exception being that if you buy a used card, coming up on 10+ years old because your requirements are minimal - don't expect current driver support. Nvidia drop support for old cards on Windows too.
AMD is definitely night and day in terms of meeting the free software ecosystem properly, and so arguably the reason to go with a new AMD card is voting for that kind of support with your wallet.