Comments on https://lichess.org/@/heroku/blog/proposal-a-roadmapprogression-system-for-beating-bots/NWBa8g8j
For some bots this would work. However, unlike chess.com or others, lichess bots can be created and hosted by anybody. So for example if I want an achievement for beating a 2000 rated bot I can manually change @eclipsebot to random moves from my server. And anybody could do this - clone stockfish, host it as a lichess bot, wait for it to get an insane rating, then have it play a game against yourself and beat a 3600 rated bot. So this could be done if we have someone reliable to host bots, but currently we do not.