I think that burning coins is a solid way to do it, but I think there will be other ways as well. You basically have to prove that the asset can't be farmed by bots, or if it can it has heavy resistance. A token burn guarantees that bots can't farm the asset.

However, there are many assets (like World of Warcraft gold) that still have value even though bots are constantly plundering the economy. We only need "good enough" solutions, just like Bitcoin did for the byzantine generals problem.