> But the M4 Pro Mini has a significantly faster CPU, much faster GPU, much higher bandwidth, quieter, cooler.
For 4000€ with just 64GB of RAM instead of 96GB and the same 4TB of storage. So, sure it might be "significantly better" but at 3 times the price that is the bare minimum.
Side question: Lots of mini pcs accept usb-c PD input, i.e. your external PSU can be any laptop charger. Does the mac mini support that?