3600's are still perfectly good gaming CPU's even when paired with a 6800 or 3080 and especially at 1440p. In fact, there's
no practical difference in frame rates at 1440p and up.
The main problem is their price as that's come back up in recent weeks so $US190 seems a good price. If it should go back up in your area I can expect 3600's will only drop back down as 5600's get more numerous in the marketplace. It's really your choice how much you want to pay for no practical difference in 1440p fps.
In general, the 'best cpu' for gaming is not very relevant and hasn't been, really since 2nd gen Zen processors. That because it's only significant on even the best GPU's at super high frame rate gaming (e-sport type games, think Rocket League and PUBG) and generally at low resolutions (1080p). Even then slim enough margins separating the top FPS 'scores' (150 vs 180fps) make it unnoticeable to all but the most selective of 'golden eye' players. The top processors are close enough that being crowned 'best cpu' is only a title and a marketing ploy.
To me what's more important was how it brought down the price of high-end CPU's to make it affordable to the average gamer. So seeing how Zen3's been taken over by scalper's charging premiums is really sad.