Synology 918+ here. Four 4TB Ironwolf drives with 256GB NVME running as Cache. 6GB of system RAM.
About half of it is for just backup of files (pictures, etc), not quite another half is for running a virtual machine (Cache server) and the rest is running their surveillance station app and recoding a couple of networked cameras.
Zero complaints so far. Setting up the cloud backup so it automatically syncs with my Dropbox is just soo nice...