For me, anything 25 FPS or higher is 100% fine and I’ll be enjoying my time. I never play competitive online shooter games ever, though. All single player ones like GOW and the likes. I game on a 60 Hz 4k monitor. GPU is AMD RX 6600 alongside Ryzen 7 5700G and 32GB RAM. My games are set to meduim most of the time at 4k. Demanding titles are on low. Surprisingly, GOW and GOW Ragnarok are both set to ultra and I still get around 40ish FPS.
Anything realtime needs to be at least 60 fps, the closer to my monitor 144Hz the better. Something like a city builder or turn based strategy or non-time-critical relaxed co-op stuff is fine to be 30+.
I’d never want to play any shooter at lower than 60, no RTS, no racing game and so on.