No, you're misunderstanding. Linux supports new and old. Windows only supports newish. Gamers are more likely to be on newer hardware and so the end of win10 will still allow them to upgrade to win11. They won't have obscelecence. Older PC users will have forced obsolescence due to win 11 requirements and the eol of win10.

So, while I expect Linux use to rise with the end of win10, it won't be mainly gamer PCs. Gamers with a steam deck, already familiar with Linux might be included but that's a tiny demographic.