A close friend and top 35 EWS rider was talking about this from a different angle. I had just bought a new 150/140 FS trail bike, and he said take all settings off, set sag and then dial in the manufacturer’s compression and rebound settings appropriate for your weight.
Then ride in the centre of the bike upright as much as you can, it will generate grip at both ends, if it feels “ mushy “ at the back, then you are not riding in the centre of the bike!
Many folk, instead dial in more compression damping and more rebound damping to compensate for poor body position, thereby reducing rear end grip particularly over low speed chatter, or claim the shock is no good and swap it out!!
Rider error not the suspension/ shock..... the old saying “ poor workman blames his tools” springs to mind.
His final comment was try to ride the bike off the pedals through the bottom bracket like a polo pony rider!