Same issue here. Tried all the usual stuff to improve CPU performance. Everything works fine until I get into a close quarter gun fight, FPS (CPU side) drops, resulting in larger TN, resulting in things sliding, rubber banding.
Also often happens when in vehicles, but likely similar problem: high CPU load -> can not keep up with server.
I play on a 7840U laptop CPU, 32 GB ram at 6400 and an eGPU 3060 TI. Not the most ideal setup but I would think I should still be able to have a playable game at 45 FPS. The standard should not be that if I can not run a game at 60FPS, I can not play online.
Note that I have tried lowering everything to bare minimum, even rendering. Same issue. The base CPU usage of the game is enough to cause this issue.