This is a wall mounted (screwed in place) holder sized to fit either an M1 or M2 Mac Mini (or other size-equivalent Mac Mini I suppose).

I made it with the intention of the Mini being back side up (that is, the Apple logo is upright) so the ports point up but more importantly the fan duct also points up. 

This is the best solution for heat management even if the cable management may be a little less elegant, but the model is made to allow for mounting it upside down (with the ports pointing down). All ports remain accessible in that orientation and the power button is still usable as well (although you will need a pencil or something similar to push it).

The Mini should fit in place very snugly, it slides into place with no real resistance but is held very nicely.