No idea. But that's not what I meant.
It is a stage performance for an audience, done by people who make their living acting (or so I'm understanding). It is completely different than 99% of the D&D games out there being played.
While they occasionally have a session in front of a live audience, as do other streaming shows (such as Acq. Inc.) the vast majority are simply streamed. I think you’re assuming more artifice than there is, they’re simply very good at improve and voices and are very good friends who having been playing together for a long time.
I get the impression that many people assume this group formed to cash in on the popularity of D&D, which it did not.
But, sure, it’s not your thing and that’s cool.