> We're facing the issue in Ontario where firefighters are bored out of their minds and are being used as first responders for anything and everything. They show up to random fender benders.

It is a common misconception that the job of firefighters is just to put out fires. They have long been a jack-of-all-trades profession. It has long been normal around the world for firefighters to also do rescue, inspections, hazmat operations, etc. 'Rescue' itself is a very broad and commonly needed function, which may be more common than actually putting out fire these days.

They are typically well trained in a huge number of things, for example you say hazmat.

Even if they can't handle it, they know who to call and how to report it. An EMS is going to be far less capable of identifying many kinds of chemically hazardous situations. Police officers are more of a mixed bag and typically do the "lets push people away from here to be safe so someone can identify the problem".