Given bounded resources, there might always be a "shortage of EMTs". Some rural places for example don't have the funds to even support one (and an a couple of emergency situations can peak demand even in bigger cities).

The shortage might be at the root of the problem, but it also might be unavoidable. It's not always a given that a shortage can be fixed (or when it will be fixed). And given a shortage, people who call ambulances for no reason (which very much exist) make things worse.