I think DM is actually UNDERRATED by most top players because they either a) take their own DM for granted once it becomes second nature/muscle memory, or b) play against other people with sick dm and therefore rely more on timing, coordination, map pool etc. to win
The thing is, it's theoretically possible to have godlike dm but be so dumb and antisocial that you can't hack it in invite/prem, but that's omega outlier status. If you grind mge on a class like scout and meet an absolute bare minimum for comms/not feeding your ass off you can play at a decent level.
I'd also add that there are players who are perceived to have succeeded at a high level due mainly to gamesense (like blaze), but still had totally acceptable DM for invite: you'll almost never find an example of someone succeeding at the top of invite with outlier bad DM