Threading makes channels far less noisy for me. Especially the larger the channel is. When is just a few people I don't need threads. But >3 they are great and help organize. The greatest thing about them is also that you don't have to use them!

Slack itself has a large amount of issues beyond this. Notifications (ringing my phone hours after I answered a message or not notifying me at all). Not dropping you into threads for notifications and many other things.