Yeah, never heard that one before.
I can see why it made you suspicious of the care she can provide, it totally would have made me as well. I'd definitely be shopping around if I were you and there were other options in my area. (For the record, Peanut's AV and even the desperation "exotic" vet she seen think foraging and other enrichment opportunities are fantastic. Peanut's primary vet loves that she has so much to do, I really get the impression she sees a lot of small birds with lacking care.)
I will say the same thing a friend said to me when I had a similar rant when Shadow's vet recommended an utterly rubbish dog food years ago: Care for the animal isn't always the same as the medical treatment for that animal. The food was terrible advice but the level of medical care my dogs got at this place is the best I've found in my area. So occasionally they will recommend some care I find questionable but are never disrespectful of me when I ignore some of their advice. (Which sounds like a major problem with this woman, that she knows she is right and doesn't respect decisions you've made, whether she agrees with them or not.)
So I guess ask yourself, are you happy with the level of treatment and how they care for you and your birds? It sounds like no, and that is good enough reason to try and find someone else.
Edit:
Also, I'm so sorry for your baby. I hope she feels better soon.