Let’s explain things.
People want bans because of mana cheat. Well, it still gets printed, and other cards that mana cheat remain untouched. Cards that do the same still get printed. Making banning unnecessary. Add in reverts which make little sense (look at naga sea witch who remains nerfed while avianna is free to roam).
People want bans because a deck is broken. Well several decks exist which were broken and required adjustment. They avoided modification. Making banning unnecessary (see pirate rogue, mech mage, mech rogue, even shaman, palladin, shadow priest).
People want bans because of OTK issues. Well several decks exist which were broken and required adjustment. They avoided modification. Cards that do the same still get printed, and other cards that OTK remain untouched (see complaints regarding mage). Making banning unnecessary.
The ethics behind banning evades me. It is a blanket. Instead of adjusting issues as they occur they ban. They may as well reduce mana cost from cards that are 7, 8 9, 10 do nothings. As they are highly unplayable.