We use Meet at work. As far as I can tell, it's just Hangouts, but with a lot of stuff removed like the good chat integration that Hangouts previously had. I think they rebranded it B2B to try to kill it off to not compete with their new Duo and whatever else consumer offerings no one likes.

Bet they are kicking themselves now that Zoom ate their lunch in the pandemic. If they hadn't killed their consumer offering, they would have been well placed like Zoom was for a massive traffic boost. Bet whoever wrote Duo to replace Hangouts got a promo, though!