[fps]

This seems like it's going in circles, but, if you selfsign modern browsers display a big scary warning. If you're making a device or software meant to live behind a firewall and to be accessed from a browser, users will either have to install your CA in their browsers, or deal with the big scary warning. Both of which are bad.

[gsich]

If you don't have a domain, chances are that you don't provide service to normal users. Or to users at all besides yourself.

[pessimizer]

> chances are that you don't provide service to normal users. Or to users at all besides yourself.

I think that's the point. Creating friction that scares normie users when people are using web UIs on local networks puts non-cloud based products at a disadvantage against the centralized giants.