This has been the classic answer since free demo CDs back ik the 90s.

I guess it qualifies as retro now, so they are not nerdy but stylish.

The screenshots look like it now takes more clicks to get to groups/conversations than before. That appears like it will make me less productive instead of more.

I hope I’m wrong about this.

Discord is easy to setup and use. It’s basically a chatroom with history. It can help build a community. It’s also a horrible way to store/archive information because it focuses on real-time communication. At larger scale it also tends to get too noisy.