Earlier quoted context omitted.
The context here is the article's author is a twitchy FPS player, those extra 3ms are something that community agonizes over. I appreciated how much effort was put into controlling the variables in this test. There's a whole lot of witchcraft associated with these kinds of efforts and he sat down and did the measurements and got real numbers. My hat is off to OP.
ping is going to dominate over 3ms in pretty much every situation. And the non-xwayland numbers are all within a single ms of each other. --- Not to undermine the measurements of the author (agree with you, it's a cool effort), but my read is that this was basically proof that it doesn't matter.
There are weird consequences of this, someone can shoot you after you duck behind a wall because you hadn't yet in their version of the game. An enemy moving left right repeatedly is likely vibrating in your version of the game faster than the rules of the game would otherwise allow. Etc. Ping matters, but it's not comparable to input latency. Input latency really does mean that you can click at the right time and miss your enemy. It really does delay how fast your camera spins when you move your mouse. Etc.