My mind goes to simple solutions like established communities having a $1 entry fee, for privacy use a privacy crypto maybe but that's a decent amount of friction for average folk with the current UX.

Another interesting idea that comes to mind is that every post/comment made needs the user to physically use their fingerprint scanner on their device which I assume plenty of devices have already. As long ad it can't be spoofed it works but not sure about the details about reliably securing that.

It would be some friction but I feel like it would be fine?

My friends just booked a trip to Hawaii on booking.com and they were each shown different prices for their hotels: $1300, $1500, $1700

Ridiculous.