Xiaomi phones are insane, at least BlackShark. They replace virtually all the major user level stuff of Android with extreme data collecting alternatives. They then make it so that you cannot disable many of them (via adp, custom ROMs etc.) without bricking the phone, I'm talking wallpaper or clock apps that run with full, non-modifiable privileges. They subsidize cheap hardware with truly insane level of tracking.
They will also stop allowing custom ROMs once they've built up enough reputation, some newer models already will never have custom ROMs.
They will also stop allowing custom ROMs once they've built up enough reputation, some newer models already will never have custom ROMs.