The thread link points to the fixes and enhancements brought by the December update. At the same time there’s also a feature drop for Pixel devices, a summary of which you can see below:
For now, Video Boost seems to be exclusive to the Pixel 8 Pro despite it being done on the cloud.
I feel like that has to be where it expands to next. It seems like this is a way to add a feature to the pro model in order to justify the cost difference.