People risk or sacrifice themselves to save others with some frequency. Just a week before Ulvade, Dr. John Chang gave his life to tackle the shooter at his church in Orange County. Bravery exists. The belief in bravery is why we give special privileges to law enforcement. If we knew that police would never put themselves in harm's way to save children, we would never tolerate law enforcement as it currently exists.
In the Commonwealth a police officer would likely get a George Cross for extraordinary bravery (the Victoria Cross is the medal for extraordinary bravery in the face of the enemy and so accordingly it is awarded to the military). New Zealand police officer Stewart Guthrie was awarded (posthumously) in 1990 for confronting a gunman who'd killed a dozen people. Guthrie warned him, "Stop or I shoot" but the gunman shot him first.
But of course such awards are rare because such events are rare in Commonwealth countries.
If we hired every one-in-a-million hero as a police officer in the US, we'd have 165 police officers.
There's about 700,000 police officers in the US, and we can barely hire them as it is.