No your point is that you think someone laying down on the floor isn't a threat this is incorrect.
A single compliant suspect who hasn't attacked anyone laying down on the floor because they have been told to do so surrounded by several officers is unlikely to be a threat.
A violent attacker laying on the floor who's seriously injured several police officers and wouldn't go down till they were tased is a massive threat to an officer until both they, and the other person that's attacked them is in handcuffs.
This is real life, not some tv drama.