IMHO since phones are basically minicomputers now anyway, we should be able to install whatever OS we want. Heck, being able to dual boot would also probably be nice.
I currently use an Android phone coz let's face it, iPhones are overpriced. It would cost me half a year's expenses on food, etc.
The sooner Huawei release their own OS the better as far as I'm concerned. It will open up an alternative to both Android and iOS.
Regardless of which OS you use though, data mining is here to stay and it boils down to which OS and apps you feel more comfortable with.
Yes, we do need alternatives though I'm not keen on anything from Huawei.
Custom stock ROMs are available but it might damage your device as well so not recommended for common user.
Huawei might introduce of google doesn't accept them but recent news says restricting huawei will cause economic crash on USA so there will be some compromise soon between google and huawei.