Read postscript.
It does matter. Also, it's not just about "good" gaming chairs and tables. It's about familiarity.
Trust me, to experience this, you need to be pretty good in a game that involves mechanical skills. Valorant and CS are not even the best games to portray this. Rhythm games like osu! are much more apt.
Play in the normal posture and position you play and then shift your chair just 5-10cms outward and try to play again. There will be significant changes in consistency. You can still hit crazy flicks or shots, it's just the consistency with which you hit it reduces.
Of course, people in silver-immortals (valorant) won't feel a lot of difference. But in pro play, it does matter.
Although in this context it definitely is bogus because VLT matches do not start till a good week. It takes 3-4 days to get used to a new setup. Still, it seems they are not taking risks.
Ohh btw, if you think that who cares about such minute details, VLT certainly does. R2Ace definitely cares a lot about these things. VLT prefers only BenQ monitors, and whatnot.
Definitely differences in playstyle and preferences. VLT is filled with veterans and old CS players. GE has all very young players (mostly under 23) except Kappa. All this does matter to them at pro play level.