>That isn't a NAS, then. It's a home server.
It's just 2 different usages of "NAS" for different contexts.
In a business/enterprise environment, "NAS" is a more constrained definition of a single-purpose rack that only does storage duties.
However, in a home environment, "NAS" is a fuzzier definition to also include running "apps" like Home Assistant, Plex/Jellyfish media, or webcam video analysis. Either in containers or vms. Both the vendors Synology/QNAP/UGREEN and the consumers use "NAS" in this looser definition. If you go out on Google search or Amazon to search for a "home server" to buy, you will get "NAS appliances" as the results. This happens because a NAS in a home usage has plenty of idle CPU leftover to run extra apps that's not strictly just storage. Buying a 2nd computer to run apps just to satisfy the NAS to remain as a "pure" NAS is a waste of money.
Similar situation to "routers". Business/enterprise routers are single purpose. But home routers from the ISP are fuzzier definitions. They also include a DHCP service, a firewall, and a Wi-Fi access point. Maybe the home versions are not "true pure routers" in the official OSI 7-layer sense. Ok, but home users still call them "routers".