This seems like an interesting product for tinkerers and hobbyists, or possibly for educational purposes (e.g. Linux computer for university students to learn on). I find it hard to see how this can replace a more typical small desktop computer though.

What sort of things are most people doing on their desktop computer that needs more power or RAM though? I can't imagine.

You can still buy woefully underpowered laptops with hopeless resolutions and with 4GB of RAM running Windows 11, and that is a horrible desktop experience. At least with this it is a usable desktop machine, where the normal bottleneck was IO speed.