They didn’t really have a choice. They were building on open-source software and Linux and Arm are somewhat bad at abstracting the hardware. So this means that the manufacturers must homebrew their own distro for their hardware, instead of just publishing drivers like windows hardware does.
They’ve been working on fixing this, but fundamentally they built their castle on sand. And if they hadn’t, they probably never would’ve gotten anywhere at all and we’d all be on Blackberry or WebOS or WinPhone or whatever.