Points 2 and 3 and just innate to the project, not something that can be fixed in a custom ROM. Point 1 is not something any of those projects choose to fix, you need to either root or use a particular ROM to get around that because of how baked into the network stack those limitations are.

We really need an open source mobile operating system that isn’t controlled by tech megacorps.

Android is far too compromised by corporate profit motives.

• it helps network operators identify tether traffic and prevents it from being hidden by the systems VPN.

• it facilitates vendor pre installed adware, bloat ware, and malware that can’t be uninstalled

• it facilitates carrier locking to prevent users from switching carriers