IMO, it's the perception of attitude when introducing new and wacky ideas. People seeing these new ideas say "that's wacky/bad/misguided/wrong/etc" and the defense (used to, anyway) fell back to "our HIG says this is the best way" (paraphrasing). To then recant years later and reverse things just makes it harder to accept any new ideas that come out as received wisdom.

If they had a 'wacky new ideas' branch for people to test on, I suspect the whole thing would be received a lot better.