The Ban system has been used as a crutch for years now
A balancing crutch, as it happens.
The intended purpose of the banning phase was to strategically remove champions from play that would throw a wrench in your team's intended composition. With only a few exceptions, this game wholly lacks the hard-counters found in its predecessor that the ban phase was lifted from.
Instead, it's simply used to remove champions from play who happen to be over-tuned compared to everyone else in their class. It's being used as a band-aid fix to cover up egregious design flaws and champions with too much power packed into their kits. Is that really healthy for the game? Champions like Kass were perma-banned for months until Riot just utterly curb-stomped his kit. What would we see if the overpowered folks COULDN'T just be removed? Maybe a one-month Ranked lockout on new/remade champions?
Aside from OP whack-a-mole, what exactly is the ban system doing for the game?