The new version of After Effects (23.0) appears to be causing some issues when opening After Effects project files if you have an NVIDIA GPU. This issue has been addressed to Adobe, and the issue will hopefully be fixed soon in a future After Effects or NVIDIA driver update.
In the meantime, here's how to work around this:
In After Effects, try the following:
Go to Edit > Preferences > Import
2. Disable the tick box "Enable hardware accelerated decoding"
3. Go to Media & Disk Cache > Empty Disk Cache...
4. Clean Database & Cache
5. Go to Edit > Purge > All Memory & Disk Cache... and press OK from the popup
Kindly note that if you encounter this problem with a Motion Graphics Template, you will need to revert to a previous version of After Effects from the Adobe Creative Cloud Desktop Application, and run the Motion Graphics Template again.