There's a sea shanty called the Wellerman that recently blow up on TikTok, and listening to it I was amazed how in sync the whole thing was despite all the layers. (It uses the same chain technique, but not "live".)
Not-live overdubbing with perfect sync has been going on since the dawn of multi-track recording, although the popularity of including video from each layer (and DIY without a tracking engineer running the session) surged in popularity during the pandemic. With modern editing in a DAW, quantizing every phrase, word, or even syllable to the grid (or other layers) isn't difficult at all, just a bit tedious.
