Disk Permissions

Almost none of the previous OS versions needed to repair permissions. It was mostly Voodoo.

Home folder permissions would get messed up occasionally, but Repair Permissions never fixed those. Repair Permissions only acted on system files. All of those files have been protected by SIP since at least High Sierra, maybe even before that. The system permissions were almost never corrupt, and now they cannot be affected by rogue third-party software.

That was removed a while ago, maybe prior to High Sierra. There is no need to repair permissions as they cannot be changed anymore.

If you did something to your home folder permissions, this may work in Mojave.

Resolve issues caused by changing the permissions of items in your home folder - Apple Support

will concentrate my efforts on looking for a disk repair utility in case I needed it, just t have it for emergencies only.

You'd be better off with a good backup strategy.

Disk Utility will repair most problems. If they are so bad that Disk Utility can't repair them, I would abandon that drive and get a new one.

Do you run Disk Utility often?

Virtually never.

A Mac is designed to be used, not maintained.