I'm curious how much more expensive, though - the low-end mini is $600. I don't know how much each of the OPis is once you've added all the accessories to make them functional, but it wouldn't surprise me if all of performance/$, performance/watt, and actual total cost winds up being better with the mini once you've got more than one or two of the OPis running.
A 16GB RAM OPi5 is $140 and a 16GB OPi5+ is $180, outside of sales. Both of my OPi5's have a small microSD boot volume and a 1TB NVMe drive that cost about $50, because when they're not doing arm64 builds for my GitHub projects, they also do some Longhorn volume replication in my home k8s cluster. My OPi5+ has a 2TB NVMe drive for video recording-to-disk. (I designed and 3D printed my own cases, so I didn't factor that in.)
A Mac Mini that matches the important specifications here--and CPU performance isn't one of them, but memory capacity and disk storage are--is twelve hundred dollars. Before you add a capture card or the additional terabyte of storage for the video capture box. Also then I'd have to fight with Asahi Linux or something, because my workflows, while probably portable to macOS, already exist on Linux.
I have no problem buying Macs, I have plenty. The Mini is not a replacement for the needs I described. The more general Ryzen mini-PCs are better competitors, and if you need more and faster compute are a better call at ~$230 to $400--a far cry from the Mac mini's pricing.
