Playing at their table is a losing game, the house always wins.
The reason why no one runs AOSP is because the phone market rewards differentiation. Each phone manufacture wants to build their own experience and building on top of AOSP is how they do so.
Is it really a losing game? Building a new OS from scratch is not worth it. Why throw away an entire app catalog for your device? Consumers want access to existing app catalogs when buying a phone. If anything is a losing game it's building a new mobile operating system over forking Android as a base.
This is what empire-building middle managers say to rationalize their boondoggles, but in actual fact most customers can't even tell the difference between two different vendors' Android skins, definitely can't tell the difference before they buy one, and the way they actually differentiate phones is on real hardware differences that show up in the specs like the camera or performance.
The hardware company's idiosyncratic fork of the software is irrelevant at best and annoyingly irregular in the common case.
You forgot about one thing they care about above all others — cost.
And the easiest way to keep costs down is through "alternative revenue streams", which involve your own tracking, your own app bundling deals and your own App Store, which you're pushing on users constantly. And if you do that, you may as well get the branding win from doing the custom skin too.
No, the reason is that AOSP doesn't even include a functional keyboard nor a functional call manager nowadays.
AOSP apps were abandonned around Android 11, you can't just keep them as is for real users, it looks amateur.
Even the open-source ROMs came to the same conclusion eventually and developed their own.
No one was using those apps so it didn't make sense to spend time on them.
Don't be a prick.
Assuming you can get a hardware vendor to support your fork.
Android has always been a weird blend of proprietary BSPs wedged together with the core AOSP project - we used to have an entire team whose full-time job was merging the Qualcomm BSP into our AOSP fork. At the time you didn't even get access to that BSP without inking a deal with QCOM...
Technologists need to aggressively reject solutions which don't spread freedom to ordinary users as well.
AI generating code changes the game significantly, though there are issues with that. A new OS would have taken several millions and multiple teams, but can now be done for far less. The problem is hardware to run it on. Who'd pay $2,000 for a shittier phone with less features when a $500 used one with GrapheneOS is right there? So the market, (in)efficiently, hasn't come up with a new phone OS. Not because it isn't warranted, but because the free market isn't a perfect system.
https://www.reddit.com/r/ClaudeAI/comments/1wfpydl/i_asked_c...
Android is even more of tragedy, given how all relevant NDK game development APIs are also available on GNU/Linux.