I was you up until 3 months ago. I went nuclear and focused on the more open source side of android and have been so much happier for it. Sold everything to afford the changes.
It's also cheaper consider the availability of different Android phones, I left pixel for OnePlus recently, because it decided then screen died after a small drop for pixel 5a, a phone with well known defects
Home assistant is great and apart from voice recognition, its infinitely more powerful than any corporate home automation product. Voice is tough to do locally and on low powered hardware, but its getting there.
they have something that claims to be able to do it, I haven't personally verified it, but generic on device voice recognition has gotten pretty decent.
Some phones only. Or at least that is how it used to be when I had one not too long ago. The boot loader had the be unlocked and some apps like banks or Google pay refused to work at the time (or maybe it was if you had root enabled).