The huge dtube upvotes distort the whole thing in my view. I can't really tell if anyone uses these apps (or curates their content) because there is real demand for it, or mostly because there is massive free delegation subsidizing it all. Is the game really about 'curation' or is it about catch-the-delegation-money?

huge increase of manual curation

Bear in mind that the goal (particularly of the poster here) isn't necessarily manual curation per se, it is changing voting behavior to be less content agnostic and less focused on self-enrichment with no real contribution. That could be manual curation, but mostly it means making the self-voting type stuff unprofitable so people stop doing it. If they instead delegate to even a mediocre (bot or human) curator, that is still better than self-voting and vote-selling (at least according to the poster, but I would generally agree).

As for discontinuing the experiment, the obvious question to ask is where is the money (which, again, is largely a game of catch-the-free-delegation-money) going now and why was that decision to move it made? It wouldn't necessarily need to have anything to do with the curation.

There still might be useful data there, I don't know.