Some people want to make a DIY equivalent of a Synology NAS - something to make backups to, and maybe some other light serving tasks. They don't need the GPIO, and they're not attentive enough to their power bill to appreciate the difference between a device drawing $3 a month and a device drawing $0.30 per month. They know many of Synology's products use Arm CPUs.
Later they find themselves saying hmm, it sure would be nice to have real SATA ports. Maybe a shared power supply for the drives and the CPU. It'd be nice to have enough IO and CPU to be able to saturate a gigabit link with encryption turned on. Oh, and a nice case with an active cooling solution built in.
Suddenly, a retired compact PC starts to look like strong competition.
Later they find themselves saying hmm, it sure would be nice to have real SATA ports. Maybe a shared power supply for the drives and the CPU. It'd be nice to have enough IO and CPU to be able to saturate a gigabit link with encryption turned on. Oh, and a nice case with an active cooling solution built in.
Suddenly, a retired compact PC starts to look like strong competition.