If you want to swap, then just do it right now? As far as gaming is concerned Linux just works, and reaches speeds that are more than good enough to do so, even if they're not exactly the same as windows - the steam deck is pretty much proof of this.
If Linux was measurably 5% slower on all benchmarks, would that mean you wouldn't do it even if you wanted to? Is every single nanosecond of performance really that important to you? I switched 10 years ago when things were a lot rougher than this, and in the end everything still worked well enough that I never cared to swap back.
I gave it a try. Got a steam deck, tries steam os on my desktop.
I kept running into issues that took me time to solve. I understand that the only reason it took me time to solve these issues is because I'm new to it and that people who have been gaming on Linux for years already know how to solve them all. But what would happen was is I would sit down to play a game spend maybe an hour or two fixing issues and then after that I ran out of time to play the game. I kept this up for a couple months but honestly at some point I just gave up. Now I'm playing games on Windows again.
To be clear, I'm a huge proponent of Linux gaming. I just unfortunately am too busy these days to spend the time to get it to work.
5% would already be well within the margin of difference for separate identical clean installations of windows on the same hardware.
But the issue is that it is many multiples of that, especially on the most common PC gaming hardware (Nvidia GPUs), often more than a 25% difference in framerates. Not so important at 144fps, but very important at a 60fps baseline and for genres like fighting games.
A lot of people don't mind, say, an extra 5 frames of input delay. They don't notice it. But a lot of people do notice even an extra 2 or 3.
I do think that frame pacing issues kinda do have a critical thin threshold where it's either bearable or an unacceptable difference. And the native windows version can often already be riding right on that line. So while it's not fair to the Linux version to demand better, it is unfortunately the case that it might tip over that line.