You've been on itch.io for fifteen months and published one game. I've been on itch.io for nine years and published dozens of games. Maybe don't dismiss what old hands tell you.
That said: your game is NSFW. These games have been under increased scrutiny on itch.io since this spring. Our admins say it's nothing, just basic protections against financial fraud. Other people here aren't so sure about that. Either way, the OP just confirmed what I told you on Discord: that organic traffic boosts your ranking. Also, if an affected game can bounce back soon after falling from the top, maybe that means there's no conspiracy. No secret changes of algorithm, or at least nothing permanent. Seems pretty relevant to me.