There's no question that many people successfully run SBCs and are happy with them but here's some of my biased reasons why I don't recommend ARM based SBCs like the pi, HA Green, HA Yellow, HA Blue, etc for running servers.
- They have a poor price performance ratio
- Some need a powered USB hub if you want to reliably use their USB ports, for example for a external SSD [2]
- Their internal storage sucks [1]. SD cards corrupt easily
- USB boot can be finicky and likely has to be configured:
- You need a HDMI adapter or USB C cable and a serial software to debug some of them
- You can only run specialized distros on them and hence can't easily boot just any live iso to troubleshoot or test something [3]
- You're limited in what you can run (ARM) and debugging tends to be harder
- Its hardware can't be extended/modified. For example by adding more memory or a GPU for LLM/Voice
- You can't properly (as in a pain free, supported and and in a performant way) virtualize of which I'm a big fan of [4]
In comparison. For about 100$ (SFF or tower PCs for even less than 50$ in some locations) you can get a small x86 PC with none of those deficits that can run pretty much any OS and software, can be extended with more RAM, a different CPU, or PCI(-E) devices like a network card. They are also generally a lot faster. A real general purpose PC.
- Some like the pi 5 and yellow can use a NVMe SSD which is nice. Green and blue use eMMC. The green's eMMC is not replaceable.
- I don't know why the pis can't provide reliable power via USB but it was observed many times that external SSDs connected without a powered USB HUB experienced corruption.
- In the case of the green you can to my knowledge (for now) only run HAOS for example
- Popular virtualization suites like Proxmox VE don't support ARM yet. The limited memory and inability to extend it also make this unreasonable.