Fortunately for us humans that seems to stop at 120Hz because most games can't even hold that at a steady rate with a 3090.
Now whether a 300+W gaming device is interesting in the long run will be answered this year by your electricity bill!
I don't know where'd you get this notion that it stops at 120hz. It's been proven again and again that even with monitors with low refresh rate you still get a better experience by having more fps available. Better so when you have both the frames and the refresh rate in your monitor.
Not that big of a deal when you are all getting together in real life. You can see if you were at a disadvantage due to equipment. Online, you don't get to see.
Equipment quality will always have an impact in sports.
And, at high end competitive, I don't really see a problem. Even low level, I don't see a huge problem. But it does exist. Is why I offered this as a "being fair."
[1] In a particular game I discovered that abusing the R/G/B controls into giving you something that looks almost like one of those colorblind simulations in normal conditions would give you a massive advantage to the point of most players calling hacks.
I'll be honest, it sounds like you have no idea how competitive gaming works, or any sport at all. Your comments sounds exactly like thinking one can be better at football by buying more expensive boots.
Definitely there are real advantages to running higher framerates but its all diminishing returns. If your rig is fast enough to maintain CONSISTENT frames that is probably more important than going for the absolute highest - there is a reason many set a minimum / maximum FPS target. Consistency is important.
Most of the really competitive games arent really all that hard to run either these days - even an older but still decent gaming computer can do great. Considering how cheap it is now to build something that will run most games well vs how it used to be in the past I think the pay to play aspect has actually REDUCED quite a bit. You can buy a quality mouse these days for 20-30$ that would blow away what we had 10 years ago and that mouse probably would last you for as long as you want.
Reminds me of an old racquetball tournament where they would put everyone in the same level (as in the top players intermingled with the bottom) but depending on the players skill they were given a type of massive handicap. If you were in the very top tier racquetball level they gave you a racquet that had been strung in a very clever circular way where there was a literal HOLE right in the middle of the racquet where the sweet spot was!
Spoiler: Those guys still often won
Not really new, mind. Lan parties that had that one person that spent way more than everyone else was a thing. Did they automatically win? No. But they punched over their league in the party.
Also, higher refresh will give skilled players an advantage, but it's def not pay to win.