Bronze isn't bad, people suck but you're actually free to play most heroes there and it's a fun/varied meta dominated by short-mid rangue heroes (moira, reaper, junkrat, rein, symmetra, etc.)
Personally I think low masters, aka one-trick 0% flexivity purgatory, where all the onetricks that are too good for diamond and too bad for masters are located. Mid gold and mid plat because everyone over there think they deserve better and that they're stuck in their rank because their team mates suck yet they refuse to cooperate or play anything that isn't fucking genji/roadhog/mercy.