Wow. Super impressive. Guess with today’s technology you could do it pretty much 100%. I saw that model that lets you separate music into separate tracks for guitar, vocals, drums, … Guess something like that could even separate the laughs from the next actor resuming to speak.
Kind of also reminds me of those videos where they stabilize / de-shake Star Trek. There are some scenes where the ship gets shot at for example. And the actors act that out and the camera is shaking too and a bit at an angle. Looks funny once that camera shake is removed.