Your Landlord should have a say in the proposals to change bylaws of the condo; he is the owner. Did he appear at the meetings? Did he take a stand? Did he vote?

They "could" have grandfathered in people already living there and just not let any other new residents follow the new rule. But that wouldn't have helped with the jerks who aren't picking up after their dogs.

So sorry to hear that you are having this extra stress. I don't what else to say except, UGH!