Sorry, where did you get this from? Because, either you adapted one of my memes (yipee, I did something fun!), or we had the exact same idea, at about the same time (I'm so sorry for that, in such a case).
Welp, that hits right in the feelings. I started writing a dystopian Handmaid's Tale-esque as a warning about Trump, and I had to cut out the bit of Trump dying and his successor going insane, because... he showed his craziness.
I don't know too much about distros, but you want something quite light. Let's be real, enterprise like schools won't pony up everything for Debian, especially when they just use Chromium and maybe Libreoffice. Schools are cheap, and if you can hacksaw together an Arch-based thing, they WILL buy miserable hardware, that can just barely run it, and an 8 gig SSD is much more stomachable for them than a 32-gig for Debian. SteamOS doesn't completely crash, and that's infinitely more complicated. This is basic Arch, plus a WM, plus Firefox/Chromium/Whatever.
Use KeePassXC on the computer, and KeePassDX on Android. Yeah, you need to manually sync the database (.kdbx) file, but it's 1000x safer than any paid crap. Why? Their only motive is profit. FOSS nerds? Making a strong, good program.
You could probably make a small Arch install, add LibreOffice and something either like the GNOME browser or Firefox. What people using ChromeOS want is something light (for cheaping out on hardware to schools), and basically just a way to access a browser. Plus, something something permissions. ChromeOS is marketed towards enterprise, like education. Just need the bare minimum to get on the 'net, and no more.
Yes, but they're all really bad. I'm sorry, but 99% of times, you need to do it on a computer. I've tried. All interfaces are shit.