I doubt if keeping the car garaged will extend the serviceability of cv boots
outer boots are made of rubber , some inner boots are made of plastic .
I think the deterioration begins from the inside due to the grease which gets hot and liquid .
same deal as the crankcase vent hoses rotting due to hot oil mist .
parking near electric motors will rot rubber rapidly due to ozone being produced .
parking near any sort of electrical field can have other dire consequences for the car . it can prevent the key remote from communicating .