I don't know what DeX is, but if by thin client you mean the computer is somewhere else then I would say that doesn't sound like Apple at all. Apple is the last company that seems to still believe in personal computers on the desk.
This might be even more interesting with Samsung TVs which allow wireless DeX. Have not seen this in action though.
I actually use it to run citrix receiver and connect to the corporate network. hardly ever bring my work laptop home anymore.
You also still get to use the phone/tablet at the same time while it's driving the desktop.
Of course you're still using Android apps, just inside of resizable, movable windows, and not all apps behave well or work as well with mouse/keyboard as you might like.
But you can install linux shells, remote desktop apps, etc, and basically just use it as a thin-client.
There's also a way you can use Dex inside of a window on Windows and it let you drive your phone without actually touching it or doing some weird remote access stuff to your phone.
Dex is kind of a hidden gem of the Samsung devices. Once you hook up a dock with some I/O it's basically just turns your Android device into a desktop computer.
https://www.theverge.com/23787477/apple-ipados-17-stage-mana...