+1 (my kid is all grown up, self-disclosure)
I definitely have, and would recommend it. At that age, their opinion on school is very important and if they have bad experiences it could impact them for days/months, possibly years depending on how bad it is.
Yes! Teaches your kid that they will be taken seriously if they are treated unfairly. Also, it's early in the school year and there being this many issues already means there will be more.
Absolutely! Like, even if everybody involved is totally cool, it's very possible to just have a personality/vibe mismatch, which is a good enough reason to switch IMO, and I'd consider unreasonably authoritarian to be significantly more serious than just a vibe mismatch.
I’ve been lucky to not have bad experiences, but I’ll just support you that doing what you think is best for your child is ok.