This is why memorising theory alone isn't a good way to get stronger. You need to know why the theory is the way it is so you can understand why the moves are good and how to punish opponents mistakes

Even at ~2800 in puzzles I'm sometime faced with mates in one or mates in two that are quite easy. I feel like that score doesn't mean anything and shouldn't be compared to real games ELO.

I try to walk people into puzzle-like situations. Works well for me in blitz.