I'm not sure why you would need large AI models for Immich, the face detection is pretty cheap and will run on 10 year old hardware without a blip.
I think the decision comes primarily on how much data you would like to store for Immich, if you want to go cheaply, a 100 bucks used laptop will do the job, if you have too much data, a NAS will be more suitable (and you are certainly not going to get a mac where you can plug multiple internal hard drives for the price of a NAS)
I think the decision comes primarily on how much data you would like to store for Immich, if you want to go cheaply, a 100 bucks used laptop will do the job, if you have too much data, a NAS will be more suitable (and you are certainly not going to get a mac where you can plug multiple internal hard drives for the price of a NAS)