One of the comments on IG explains this perfectly:

"Meta has been doing this; when they auto-translate the audio of a video they are also adding an Al filter to make the mouth of who is speaking match the audio more closely. But doing this can also add a weird filter over all the face."

I don't know why you have to get into conspiracy theories about them applying different filters based on the video content, that would be such a weird micro optimization why would they bother with that