[echelon]

Then have the users solve ARC-AGI or whatever nonsense. If the bots want your content, they'll have to solve $3,000 of compute to get it.

[Tostino]

That only works until The benchmark questions and answers are public. Which they necessarily would be in this case.

[EVa5I7bHFq9mnYK]

Or maybe solve a small sha2(sha2()) leading zeroes challenge, taking ~1 second of computer time. Normal users won't notice, and bots will earn you Bitcoins :)