It is not up to the OS to decide which apps the user needs running. Be it wifi scanner, vpn or some file sync process. All the user needs is a correct tool to know which app consumes what, and then there User must decide. Not some prick in google or xiaomi or samsung or whoever else.
Your macOS has an unacceptable battery life already despite having a massive 58WHr battery - about 3.5x the size of a normal phone battery. Phone users don't want to lug that size of a battery around just to get battery life that's worse than they get right now from a 15WHr one.
Heh, not true anymore with the new M1 lineup. I was skeptical but they are insanely efficient.
But the two big challenges there are:
- odds are the first several iterations of it will suck, so they'll be competing with an already-working solution that most users have no concerns using (significant market uphill fight, with the only major value-add being "We're not Google").
- we've just traded one master for another. Ultimately, unless someone builds an open-standard at the Android distro level that includes an API to allow users to establish a notification source, the distro owner still owns the notification system (and there's no reason a priori to assume they're less evil than Google). And designing that API to be abuse-proof would be a challenge; do it wrong, and we're back to the bad old days of sub-one-day battery life on an idle phone.
It'd be a hell of a cool project for someone to take on though.
Even correctly behaving apps will consume much more power and network with this scheme.