Android security in 2016 is a mess
One of the major major major issues is the hardware itself.Let's jump back to the late 90s. You want to try Linux. You might partition your disk, or build a different machine and get a KVM or use an old laptop or add a second hard drive. In all cases, you can just install a Linux distro and see if it works. Maybe Ethernet or sound or something doesn't work. You could try a different distro with a newer kernel, maybe compile your own kernel with the modules you need, etc. But no matter what, it would at least boot (usually).Intel x86/64 is a standard architecture. EFI makes the booting process even easier (although some motherboards still fuck this up; but for the most part fiddling with efibootmgr and turning off TPM will work. If not you can always turn on legacy BIOS and use the MBR). ARM is not a standard architecture. It's a spec that is sold to companies who all make their own SoC templates. There are things like Device Tree Config that make some of this more standard, but it's still far from x86/64. Just read Torvalds rants on ARM to learn more.Even if you make some standard Android builds with all the drivers for all phones in a massive 20MB initrd, a lot of kernels are fundamentally different with the way bus connections are defined. Manufactures take forever to release their kernel code, often under threats by people for GPL violations, and even then they are filled with tons of binary blobs and shims that connect their .o files so kernel calls.Stuff like Plasma looks amazing. It only has like two phones it supports. If you look at any android rom project, you see totally different builds for every single device. If Intel had been like this, Linux would have died off in the 90s, for both servers and desktops.Device manufactures depend on you buying new phones. They cannot support phones after two years or else it kills their profit margins. Planned obsolescence like this leads to waste (don't kid yourself, e-waste recycling gets shipping to Africa where kids remove components. A small percentage of phones actually get recycled).TL;DR Mobile phones are based on unmaintainable and non-standard hardware (intentionally). I wrote a post on this a while back:http://penguindreams.org/blog/android-fragmentation/