The way I see it, this is a "toy" (for the time being). The "2013 devices" makes me thing that this is a "toy" for people like "us" that have a Nexus rotting away somewhere and "it would be cool to fool around on your 30-inch screen and nothing more!
It would be better if they would up-front say "this is not secure", "this is a demo", "this is a toy", "this is not the OS you're looking for".
Imaginary CEO-CTO dialog:
CEO: hey! I just read that we can throw away the PCs and replace them with some old phones that we can buy for $50 on ebay! START!!!
CTO: but.. let me explain.. I quit!!
I'm writing this on a 2013 Nexus, thank you very much! A year ago it stopped booting and I tried searching for a newer, comparable tablet to replace it: no such device exists. I ordered a replacement main board and couldn't be happier. Until someone makes a new 7-inch tablet with a full HD display, it will continue to not rot in my hands for a few more years.
This isn't just "unhardened", this is a lack of basic security, and after Mirai, nobody should be doing this shit.
As a gadget enthusiast, I loved tinkering with it. But it is simply not practical for daily use (yet). I think it could end up being a nice FOSS alternative to Microsoft's Continuum project, especially if the developer can get it working on a newer device.
Bolting on security later seldom works well.