Bug Info: All game modes, all cars, and all tracks. Since update 13 in I have begun experiencing many large drops in frame rate or stuttering. The hotfix helped a little bit but the game still slows down dramatically and seems to be getting worse since update 15 today.
Platform: Series X
Edition: Premium
Account: solo account
Peripheral: Series 2 Elite controller
Settings: Performance mode, North American region
Xbox Settings: Happens with and without quick resume
Attempted fixes: I have rebooted multiple times and opened a support ticket
Content Update: This has been happening since update 13. The hotfix helped and it has slowly gotten worse since Update 14 and 15