Avira > chazal’s authority in all areas
you have to be more specific on what you mean here. chazal’s authority is collective, of course. We have amoraim presenting a position, but then rescinding it when someone else brings a baraita. This is normal. There are many social takanot that hinge on the result.
Say, R Huna would buy leftover vegetables at the end of the market day. But, now farmers have cellphones and abuse it by quickly sharing the news and bringing more vegetables to sell to R Huna. Will R Huna insist on his minhag or change his policy?