Lubicating rubber gaskets in garbage disposall?

There shouldn't be any. Not around the motor shaft, that moves too fast to have used an o ring. And not sealing the pipes together either, you don't lubricate those.

Aside from making sure no food is left in it, there's not much to do. I suppose a spritz of lubricating oil in the drain might keep moisture off of the blades and inhibit rust but I don't know anyone who does that.

I am not sure what you read or where.

I will share this. A family member formerly spent the winters in Florida. The disposal never worked when they came home. We started adding a 1/4 cup of cooking oil to a dry running disposal on the morning they left. It solved the problem with no ill affects.

YMMV