This is completely dependant on access frequency. Do you have a bunch of different people accessing many files frequently? Are you doing frequent backups?

If so then yes, keeping them spinning may help improve lifespan by reducing frequent disk jerk. This is really only applicable when you're at a pretty consistent high load and you're trying to prevent your disks from spinning up and down every few minutes or something.

For a homelab, you're probably wasting way more money in electricity than you are saving in disk maintenance by leaving your disks spin.