I agree. It was harder to play non-adcs back then but it was still doable. Also Riot had said they wanted to make adcs non-mandatory but 8.11 wasn't meant to do that really. They nerfed adcs because of ardent meta (still dumb af) and they overnerfed so mages started being played. Then Riot was like "oh we didn't really expect this, this wasn't our immediate intention".
I maintain the opinion that Riot did too many things at once but the idea was good:
The base stat changes / AP ratios to turrets and so on were fine. I think Riot saw from internal playtests that ADCs just had too many base stats and it made early laning impossible against them. I think it was fine to make this change, and TBH, none of this really got unwound, so clearly it ended up fine
They reworked crit items to give IE sh*t base stats and made crit into a true damage conversion instead of a big number payoff. I think this was the wrong call and it's what got reverted.
That's basically all that changed. We're finally in a good spot for crit itemization after walking back the majority of those item changes and we're in a world where mages are indeed viable bot lane and actually considered with relative frequency.