Some dev theoretically might not like a mod decision Valve theoretically makes, so the only logical solution is to expect every single dev that publishes on the platform to commit to moderating Valve's game-specific forums forever.

Yes, good moderation is expensive. Externalising that cost onto devs is, frankly, exploitative. Also, "a few anti-woke weirdos" is a massive understatement. The modern reactionary movement is heavily tied to gaming and Steam plays a major role in that.