I'm seeing threads where even for HDDs people are recommending you mount them yearly to do a full check of the data and to ensure that everything keeps moving freely.

regardless if it actually helps the longevity, it's probably a pretty good way to notice when you need another copy of the data. If you have your precious data on three harddrives and one starts thowing errors during your yearly check, you can get a replacement in good time

Superstition....