Blitz
I think that most 'players' will agree, that before one can hope to score even approaching 30-to-40% {let's say}, in '5-minute games - One should 1st prove to themselves, that they're at Least 'adequate' or 'fair' in the 'time-controls' that are slower paced.
It's another version of the famous, business world's, "Peter Principle" - Ie. "Everyone 'rises' {as in being 'promoted'}.. To their Own level, of incompetence"! ..ha!
Being newer to blitz chess, I would welcome any advice or tips....