Hello,
The team is currently investigating this issue with the performance on Mac. In the meantime, to alleviate the issue, they have recommended following these steps:

- Make sure you've updated to the latest Hotfix (21 as of this message)
- Switch to Borderless video mode (Settings > Video > Borderless Window)
- Lower the resolution (Settings > Video > Resolution)
- If the FPS are still low, turning on FSR mode (Settings > Video > Gamma Correction)