Calling players bad because they're slow at improving...

[Xirean]

that fails to account for the fact, that people DO indeed like to go into things blind at times, even savage+ content.
I dont like knowing an encounter beforehand so that the only thing that matters is strict memorisation and execution, i like to have to think at least for the first few things what the mechanic right now wants from me quickly.
If you dont want people who may or may not be blind to the encounter, make a party finder, specificy that you must have watched a guide, and do content that way.
Instead of assuming people in the DF will do that

This exact thing can be said for wanting a blind run.