How frequently does stored car need to be run?

I park a car over the winter from November to April every year; have for many years. I do not drive the car and have none of the problems that you mention. The car is stored in a well-ventilated but unheated garage. If humidity is too high, the brake rotors, drums and clutch disk, if you have a clutch, will rust but that will scrub clean again with some driving when you get the vehicle going again.

Use a battery tender, not a charger; otherwise charge the battery once per month if your battery has a parisitic drain from the computer etc. My older car does not have this drain so I have no need to disconnect or charge the battery or drive the car during the storage period.

If you live in a winter salt area, that would be another reason to not drive the car; to avoid getting it salted up. Park the vehicle well warmed to dry the exhaust system.

If you are storing your vehicle outdoors, then I have no opinion on what you must do.