An interesting take, and not very popular among the other comments, but I suppose you have your experiences and reasons to say this.

As I mentioned RAID is on the table, no problem with that. It is kind of the point to have a safer, more centralized storage for important stuff, and space for keeping media.

Speed wouldn’t be a concern. Noise is, since my apartment is very small. And reliability over time would be. Especially power cycles, or spin down - spin up events. I figured if I used SSDs, I could leave the whole rig powered on 24/7 But with HDDs I think I would probably need to turn the system off for the night.

Correct me if I am wrong about enterprise grade SSDs, but if I have the power on time and the TBW values for the drives along with the manufacturing date, ones with reasonable combination of those could be bought for a reasonable price. After some testing they could also be trusted. At what point would you expect an SSD like this to last some years in a home server environment? I am not an expert but with some pointers this should be easy to figure out, which is why I am asking.