There's literally no "hate" when Chris Avellone wrote parts of the Fallout Bible. When he wrote it, there were vague ideas of making a pen and paper RPG game out of the stuff based in part off of the Fallout Bible and he specifically stated the parts of the Fallout lore he didn't like were things like alien Wanamingos, other aliens outside of special encounters, ghosts, and the alleged reversal of Super Mutant sterility due to one line of Marcus dialogue along with the talking animals. But he never wanted to retcon swathes of Fallout 2 because he hated it.
He just had a different vision of the Fallout world then others did. Josh Sawyer had his own viewpoints. Tim Cain supposedly didn't like the Brotherhood of Steel medieval knight motifs for example.
Just because a creator doesn't like certain tiny ass parts of the expansive lore has no bearing on their authority or lack thereof regarding the franchise as a whole.
There's certain Battletech writers that have biases for certain mechs, eras of history, and factions and that doesn't invalidate their POV of things either. Same with Star Wars, DC and Marvel Comics and every other collaborative franchise. Chris Avellone stating that the Enclave accompanied the Chosen One back to Arroyo has literally nothing to do with him wanting to retcon talking animals in a vague sense when he wrote the Fallout Bible as basically a trivia/tidbit thing that might've been possibly used for a PnP RPG game in the vague future.
Stating you can't have a say on Fallout lore despite having helped develop the setting because you don't like talking critters is just asinine IMHO.