Chat is too limited bandwidth a UX for serendipity.

Chat is an unforgiving ranking problem.

There's a single channel of attention, every message must be above the bar of being useful.

That's a very high bar!

There's no peripheral vision in a chat.

Peripheral vision is necessary for serendipity.

Without peripheral vision, you can only ever do urgent, not important.

If you're going to put your whole life in it, chat is only one modality of a kaleidoscopic UI.