So I’ve been looking at upgrading my PC and it looks like I can get a better “micro” pc than my current (ancient) desktop for significantly less money than a full blown gaming rig. An example of such a rig is this.

I don’t have high gaming requirements - I play mostly old games, I think the newest games I play are from 5+ years ago.

What reasons are there for not buying one of these (over a comparable “proper” desktop)?