There are a few issues with Android devices. I have 2 Android phones lying around in my rack, as well as an Android tablet that I use as a dashboard.

1. Batteries swell over time. Replacing them is easy, but it's still harder than changing one inside a UPS hat. Most phones won't even start without a battery.

2. Software support will be awful. Maybe you'll get lucky and your device will be able to run postmarketOS.

3. There's no modularity, you're stuck with the full package. Don't feel comfortable having a camera or a microphone on a device with no security updates? Too bad, there's not much you can do about it.

Don't get me wrong, if you understand these risks, are fine with them, and Android devices cover your use cases — that's great, go for it! I just find SBCs with decent software support to be a better option for general projects.