I wouldn’t recommend a Synology NAS if you intend to stream content with Plex/Jellyfin. It simply lacks the horsepower most of the time. I should just go with a DIY solution, imo. If you just want to through components that you have lying around together, I would go with Unraid. Unraid doesn’t really care what you throw at it hardware wise.
Maybe it makes it harder to steal the tv.