I've never understood why these manufacturers keep on saying they are going to beat Apple but keep on putting Android on their phones. There's a reason you still haven't beaten Apple.
No one ever seems to be prepared to have a serious debate about this either because it’s just assumed that iOS and Android are the only mobile operating systems we can have.
BlackberryOS died off. ( after a while that was licensable for a while and didn't get traction)
FireFox OS ... started and died.
https://en.wikipedia.org/wiki/Firefox_OS
WindowsPhone ... died
KiaOS has a stable footing in low end 'basic phones '
en.wikipedia.org
There have been multiple attempts ... none have really stuck.
One major barrier to entry is when iOS and Android turn it into a 'pissing match' contest of largest App store. 100,000's of apps and billions apps sold/'generating revenue' . People's data is trapped in apps and if you can't bring over just about all of the major apps then don't pragmatically have a viable offering.
[ 100% web apps would be infinitely portable doesn't pragmatically hold water either. KiaOS getting modern Firefox browser isn't going solve their gap issue any more than it did for FireFoxOS. ]
Linux Desktop has flailed for more than several years against macOS and Windows inertia on major applications . Basically same high barrier to entry.
Back when there were very small app stores ( When Blackberry and Palm and Nokia's OS were far more dominate players there was a broader set of phone operating systems. But the 'billions sold' apps stores brought all of those down. )
Android is 'free' enough that most vendors have chosen to mild-fork Android. Try to limit cost somewhat by reusing 'free'/'open' code foundation of Linux/Android, but but a differentiating GUI on top. ( Android is not like Windows , where Microsoft basically presents all of the core GUI experience to the users. ) Part of Android's problem is that people have been trying to use it for differentiation more so than a stronger collective unifier.
Most of these phone vendors put minimal money into maintaining the OS ( in part because margins are so thin). The flow of money from end unit sales to consumers to the keep the maintenance/security up and progressing in tact is fragmented and balkanized. An individual phone vendor doing it all themselves from scratch is even higher overhead placed upon even fewer phones.
[ Even Apple is cross product line spreading the core OS infrastructure across Macs, AppleTV , watch, iPads, and iPhone. Apple unified the file system code under APFS ( to control costs ). etc. etc. iPhone isn't solely funding all of its OS development either even with Apple's abnormally high margins. ]
The 'crack' Android would need at least a couple of phone vendors to break off and collectively do an effort. The problem there is that the competition level is so high the collation would likely break down before it got major traction.
There are just a couple of 'clean ups' that Android needs to do that would help alot.
1. Google does a better job of separating the hardware abstraction layer from the upper layers of the OS+libraries stack. They have made progress but it is always going to need work.
[ Ditto for the low level hardware vendors firmware wise. ]
2. Phone vendors need to throw less money away at skinning their way into differentiation. Delivering better software services value add is more worthy of money. ( those other guys are offer no security updates after a year ... we do three. So we're better. Moves on those dimensions. )
3. Set a solid floor. Some of these $80-100 phones just need to let go to something else. Trying to cover every phone physically possible gets into a diminishing returns after a certain point. For a while there was Android One
What happened to Android One? It's hard to actually say, as Google doesn't want to talk about it. We can infer what's likely wrong, though.
www.xda-developers.com
That has stalled , but Google seems skittish to put a reasonable hard 'floor' under what is Android minimums in terms of both hardware and support commitment. It is hard because basic Android is open source so the system/hardware vendor to toss whatever they want out there ( it 'free' open as in 'free speech' and 'free bear' (as long as don't bundle the Google Play store. )
At some point Google has gotten tracked into chasing 'eyeballs' at any costs. ( the spin is make it up 'loss leader' status in ad views ). But when the margins get way too thin software quality just suffers. Not enough money to do it right and too many corners get cut ( and in an uncoordinated way because being made by different entities ( phone vendor , base hardware vendor , OS vendor , etc. )