Here are my two cents...... I fly mostly A2A aircraft which if you are not familiar with A2A, their planes feature full wear and tear and damage. I can be flying along one minute and the next I could have an engine fire (not often but it happens). Here is my suggestion since 3rd party developers are starting to implement damage and failures and that’s what most people are flying. I don’t think anyone really flies default aircraft online, maybe a few people.
proposal:
Emergencies are permitted if a flight plan is filed and in the flight plan it states the aircraft you are flying is capable of failures. This doesn’t mean you will have a failure just let’s ATC know that it is a possibility. I believe PMDG has failures modeled and so does the just flight GA line, plus all A2A planes. By filing a flight plan it will cut most of the trolling. Those that call emergency without a flight plan are subject to getting kicked or whatever. Emergencies occur in the real world all the time allowing the possibility of them in the sim makes it the most realistic experience. If anything, try it for a bit and if it becomes troll city you can always change it.