A couple of thoughts …
The fact that you didn’t realise so many neighbours had pets until there was a fire alarm suggests that pets are not a problem in your building – just the idea of them.
As for fake medical conditions, this is what happens when unnecessarily harsh rules cut across ordinary people’s needs and desires.
Make no mistake, if someone brought an animal into the building and it caused genuine distress and suffering to a resident, the medical diagnosis would cut the other way, regardless of whether or not the pet owner had permission.
It’s like the people who inflict a fake asthma diagnosis on their children just so they can lift their carpets and put down timber floors.
The real underlying problem is a culture of disdain and contempt for by-laws (hello, Airbnb!) married to a reluctance to look at our by-laws and see if they are relevant to the way we live today