Just make it financially infeasible. Spam and psych warfare require an abundance of inexpensive data channels for millions of sockpuppets and AIs. If people really care about quality web content, they'll have to actually value it by paying for it. That, and content will need to be curated; algorithmic feeds were never very good to begin with, and they will only get worse, thus they should be abandoned.

But people think it's an offense to pay $3 a month for X (Musks insufferableness notwithstanding), so slop is what they shall continue to receive.