I have an Intel Arc A750 lying around that I used at the end of last year to test whether a specific problem I was having under Linux was related to NVIDIA or something else. The answer was NVIDIA basically all of the time, but keep in mind this was around the 535 driver version.

I didn't really test the Intel GPU long enough to tell you whether I'd recommend it. It worked well out of the box, but I'm not sure whether some of the game compatibility problems under Windows mirror over to Linux.

What was very cool when I was A-B testing some of the issues I had with the AMD card though, is that you can simply shut down the computer, swap the cards and it'll boot up just fine right away. No driver installs needed as the kernel just includes it - no driver conflicts either. With NVIDIA, the driver can have conflicts when using a card by a different vendor.

Also, so far the flicker/crash issue I had under KDE didn't happen under GNOME (with experimental VRR enabled). It's too early to tell (only about a week into using GNOME), but this issue might not occur under GNOME. It's kind of hard to pinpoint what the issue is related to anyway (kernel, firmware, Wayland, KDE/desktop environment, etc.).

I reported the issue here: https://gitlab.freedesktop.org/drm/amd/-/issues/3268 and pinpointed it to weird fluctuations with the memory frequency. Just workaround so far though, no fix.