Comment by dysoco

Yes, this was the ideal system for a social network imho, but it should've been integrated into an already existing network, G+ was in an odd spot between Twitter and Facebook.

Years later they briefly added Circles to Twitter and I thought that was great, not as useful as G+ Circles (since you could only have a single "private" circle to share to) but I very much used it and my mutuals as well... just to have Musk remove the only useful feature they had in years.