It all seems a bit nonsensical now being that the officer(s) involved were fired and the main cop is now charged with murder.
What if the guy who died was a white guy and the officer was a black man ?
Floyd was physically resisting arrest which took three police officers to take him down.
The bystanders that were close by watching the event and voicing their own opinion were causing some interference which might have caused the police to loose focus to what they were doing.
I dont think the main cop was really trying to kill Floyd but he lost awareness how long he had his knee on Floyd's neck causing to him to loose consciousness.
If he is charged with murder that would be an injustice to the cop, involuntary manslaughter yes.
If Floyd's autopsy reveals he was high on drugs which facilitated his death, this is going to make even more a difference in court..