So I have some issues with the video.
First off: The poster is very biased. He spent more time talking about Biden's walk, camera editing cuts, and inserting movie clips than he did the actual thing the video is about. He also insults the man's walk. Now, that's just petty and really makes me question the validity of the video.
Second:
This actually looked more like an insert than a greenscreen. The mic goes from foreground to background back to foreground. Which doesn't make sense unless you are inserting the damn thing into the video to make it look bad. Third, when Biden's hand goes in front of the fuzzy (and very very blurry) blob, it and his jacket have a dark, black line. Like someone literally cut it out frame by frame and did it with all the skill and grace of a 5 year old cutting paper.
Third:
The video is low quality: A trick often used to hide editing imperfections when amateures insert things. Given that the original is likely recorded from a news camera and is not such low quality, it makes me suspecious.
Finally:
That's not how green screens work.
I assume all the press are not really there and its all fake questions by fake voice actors that the MSM, like Fox and CNN, simply took from some other source and used it because otherwise it makes no sense why you would need to.
Then there's the technical level. To do this you would have a foreground and background layer. The background would be things behind him and the foreground would be the mics waving about since they should be in front.
So its very odd that they would have ONLY ONE MIC that switches between foreground and background within seconds. It really doesn't make any sense.
Honestly, if it wasn't for RAMA's video, I'd have assumed that it was a hoax video made by some no talent dick to make Biden look like he was faking a press conference. I mean, it probably was, but at least I can be fairly sure he didn't alter the video aside from lowering the quality.