Slow is relative.

Are you trying to compile 1GB worth of code or load into memory 4GB of game at startup: absolutelly, they’re slow.

Are you serving a compressed 1080p video file from your NAS to your media player over 100Mb/s ethernet: they’re more than fast enough. (Or to put things another way, trying to fit your home collection of media files on SSDs in yout NAS is probably not so smart as you can get almost 10x the storage for the same price and the bottleneck in that system isn’t the HDD)

You’re not going to put a massive production database of a performance criticial system on an HDD but storing “just in case” in one your historic of RAW images files after you’ve processed them is probably the smart thing to do.