I feel the same way and experience the same jerkiness.
For one I am not used to this driveline and I have other cars that Rev to 9000RPM and I can downshift at 4-5k RPM safely because the engines RPM will spike higher and not be a huge deal. The Camaro is a not happy doing that.
I tried downshifting on the Camro from 3-4500 RPM and it locks the rear up and skids dangerously. Going from 4th to 3rd, or 3rd to 2nd and were talking speed below 60MPH
Driving this car is an entirely new experience because its so unrefined compared to other cars I have and owned. I do hope things get better.