I've played probably 100+ runs of the game now (game time is wildly inaccurate as I mostly play offline) and never have seen a difficulty setting, despite seeing difficulties mentioned in discussions. Was it removed at some point?

I'm playing on Deck and feel like I've probably hit a personal skill roof with a controller, and would like to just beat the game a single time :) I've only made it to round 16 once and usually choke around 7-10.