I think this is the best solution for moderately sized and mostly-responsive groups, especially when the conversations aren't really important. This is common with groups of friends.

However for larger groups and cases where you get more async communication I find it falls apart. In this case I like Zulip's approach of forcing every conversation to be a thread more. But honestly my favourite is still email's tree of comments (or Reddit sorted oldest-to-newest). It makes it easy to follow a threads and mute threads or subthreads. Few other systems deal so gracefully with tangential conversations which I find to be very common. Of course email has it's flaws, but for async discussion between a large number of people I find the ability to see the reply-tree to be the most effective.