Anecdotally, I've a Synology NAS and any* IP camera can be hooked up to it, and there are plenty with PoE, etc so what's stopping me having a camera system at home is figuring out how to drill through 60cm thick walls made of three layers of brick, insulation and render without compromising the weather seal of my house... not lack of smart features.
ps. does anyone trust wifi cameras?
(* not quite every camera is supported)