I suppose I could be over loading it... but shouldn't there be
protection against that?

Do you know of any universal motors that have thermal protection?
The only
tool I have like that is a 20 year old 7.2 volt Makita right angle
drill.

I know very little about what features are on what motors. But I
looked on Amazon and they state that one of the Bosch routers has
"overload protection". I would think that's the same thing.

But it's not the motor that is dying, it's the electronic speed
control.