I mean if most of the champions who have these stuns and cc are insanely strong burst champions or assassins(qiyana, Neeko). CC was supposed to be a unique strength to champions and those without cc are strong dmg but now people have both cc and high top notch dmg and its not fair in any way.
In fact most of these cc are also their kill abilities(Neeko R, Qiyana R)
So in all this mess and reworks its probably best to let tenacity do its thing and if an ashe or adc want to itemize against heavy cc they will get legend tenacity and mercs treads which lowers their bot lane dueling but gives them more cc resistance also elixir of iron over wrath for more so they can be immune to a small cc duration for a purpose.
Its completely balanced and has dmg trade offs.
Tanky teams with cc take over the game and it should be counterable. even lux can opt a merc treads to lower cc of enemy laner and provide mr which results in lower dmg and more skillful optimization.