That’s not how hawking radiation works. It has nothing to do with the heat of the universe.
Basically some particle/anti-particle pairs will always form near the event horizon. Sometimes half of the pair fall inwards while the other particle escapes the black hole. The escaping ones are lost mass for the black hole. This happens for all sized black holes at all times just that for small black holes it happens really quickly but bigger black holes it happens incredibly slowly.
It will takes trillions of years to evaporate any stellar sized black hole to nothing but all black holes evaporate all the time.
That’s not how hawking radiation works. It has nothing to do with the heat of the universe.
Basically some particle/anti-particle pairs will always form near the event horizon. Sometimes half of the pair fall inwards while the other particle escapes the black hole. The escaping ones are lost mass for the black hole. This happens for all sized black holes at all times just that for small black holes it happens really quickly but bigger black holes it happens incredibly slowly.
It will takes trillions of years to evaporate any stellar sized black hole to nothing but all black holes evaporate all the time.