Pixel response time is a related concept to framerate but more about how long it takes a pixel to change from one color to the next. Usually measured in cycle time from grey to grey again, a low rate just means that images will be smooshy looking, have unclear boundaries, and end up with a 'motion blur' effect. So even if your mbp supports a reasonable sounding 120hz (8.33ms for a full frame sweep), some of those pixels will still be in transition when the next frame hits. At least, my take on it as a somewhat casual gamer.
It depends wildly on the type of game.
e.g. if you're playing a single player turn-based strategy game, you might be taking a few seconds between each decision & UI interaction. Some hard turns you might step away from the computer to think things through for minutes without touching the controls. 30fps for a game like that could be fine. 15-20fps might even be fine, especially if the game engine manages to avoid adding unnecessary input latency & is able to process input events at a faster rate even if the render runs at a low framerate.
If you're playing competitive FPS games, where reflexes matter, you'd want to get input, network & video latency as low as possible, within reason. Not high-frequency trading low. I have no idea at what point it stops making a competitive difference. If you have +100ms more latency than I do, I suspect that'd give me a noticeable advantage. If you have +10ms more latency than I do, I'm not sure that matters.
Dan Luu wrote an article about input latency [1] in 2017 where he measured latency by running experiments pressing a key & measuring how long it takes to see a response on the screen. New computers from 2017 would have around 70ms-170ms latency, depending on the model.
[1] https://danluu.com/input-lag/
I very much don't trust that article as a baseline. YMMV but I measured with a 240hz camera with a mid-high tier computer and a 144hz monitor in 2018 and a nice computer w/ 165hz in 2025 and I never got the huge latencies he experienced, I had click to photon of something like 10 frames max, so 42ms, with the average IIRC being closer to 5 frames.
input lag is a minor part of it. it depends on the game, but for example in CS2, refresh rate changes game mechanics like recoil, movement, even trajectories of thrown grenades.
i went from 60hz to 240hz, with <100fps average, and the difference was still immense. refresh rate is more important than fps, that's how big it is.
Frame rate has absolutely nothing to do with the screen you project the frames on. In competitive multiplayer shooters, frame rate matters a lot.