I would think that if a pet causes a high amount of real damage, the landlord should still be able to seek remuneration for that damage. They just can't charge for it in advance.
Urine soaking into a subfloor can easily cost more to repair than the security deposit, and recovering damages in court is hard and expensive in its own right (if the person even has money to take).
Not to mention, even when there's no apparent damage, a pet apartment can require extra cleaning to get rid of odors and dander.
It just makes sense for the landlord to price in a potential headache.
Usually it means replacing carpets, wooden floors and bottom part of walls!
Urine contamination gets everywhere , there is no way to remove that smell!!
we already have courts and torts to cover those rare occasions
Edit: right, dogs never ever urinate inside house. It is extraordinary event, that should involve courts!