Simple facts:
1. Had George Floyd been left in the back of the police cruiser he'd still be alive and in prison where he belonged.
2. Had Chauvin not kneed Floyd's neck he'd still have a career.
The reason they pulled him out of the cruiser was that he was complaining he could not breathe.
There is nothing on the side of the neck that would stop Floyd from breathing. Chauvin was using an approved technique the department trained its officers to use. The approval and training manual hit the memory hole as soon as the first shouts 'racism' and killer cops rang out. Had the crowd settled down, they could have cleared EMS in and likely Floyd would have had a chance to survive even the Fentanyl he had consumed (like most opiods, it suppresses respiration, NARCAN may have helped.)
Like the Michael Brown incident ("Hands up, don't shoot") there is a popular fable that has grown up around this one. Both fables were used to 'justify' looting and destruction, often far from where the incident took place.
While unpleasant (which is why it is an effective restraint technique), what Chauvin did was not a lethal hold technique. He has been unfairly charged, and was abandoned by his superiors in egregious perfidy.