Why is everyone saying "in this elo"

Well in this elo(means we've been here 100+ games and can't climb to save our lives, so we've seen some shit) Basically its bads justifing why they can't climb past a point, the ole blame game

Don't expect a player to dodge a blitz hook in bronze elo. Don't expect a blitz to land a hook in master elo.

Some things are just far more or less common depending on the skill level you're in. It doesn't mean every blitz will land every hook in bronze, or that one will never land in masters. The players are just better against such things through game knowledge and experience.