A significant part of the prosumer NAS market isn’t running these for storage exclusively. They usually want a media server like Plex or Enby or Jellyfin at minimum and maybe a handful of other apps. It would be better to articulate this market demand as for low power application servers, not strictly storage appliances.
Simplification is the key. My setup went from: Custom NAS hardware running vendor-provided OS and heavyweight media serving software -> Custom NAS hardware running TrueNAS + heavyweight media server -> Custom NAS hardware running Linux + NFS -> Old Junker Dell running Linux + NFS. You keep finding bells and whistles you just don't need and all they do is add complexity to your life.