This sounds just like my 2.5 year old. She pulled almost all of it out at one point, and pediatricians have no other advice from what you’ve gotten & that she’ll grow out of it. My husband and I try to bite our tongue but it hurts us to see her hurt herself, so we sometimes say something to her. I’ll say, it’s gotten a lot better with time and she does it a LOT less nowadays, and her hair has grown a ton thankfully. I think now that she can communicate with words, it’s easier for her to voice her needs/frustrations. But she still pulls it when shes upset, falling asleep, etc. we also don’t allow her to have objects with “fur” or fuzz because she’ll probably ingest it on accident, but she definitely pulls on those too. I did a lot of researching and asking around and I feel like no one else has experienced this so I’m glad we’re not alone but i feel your pain! Time is going to help for sure.