“each carspace was granted for the sole exclusive use of the lot owner to whom it was granted.”
So, the manner in which the lot owner wishes to ‘use’ the space is letting it out to another resident.
Where I am, we have a similar arrangement. It is entirely up to the lot owner how they wish to exert their exclusive use. If two lot owners find it mutually convenient to use the other’s space, why should the owners corporation care. If a lot owner doesn’t need to house a vehicle and comes to an arrangement with another resident who does need to house a vehicle, who else should care?