Why? I think chat is a terrible way to organize this information. I don’t understand why people so readily accept working in that medium. It is all for the sake of people who don’t care enough to find the proper channels, or worse yet set them up in the first place. Even for small side projects, GitHub issues is just so so so much better than an unorganized chat history. There is no reason besides laziness to not impose at least a minimal structure on your forum/support channels.
I suspect people are using it partly to deliver a more regular and visible heartbeat.
Going to a project’s discord that has active messages feels like the thing is alive, and getting engagement from the maintainers or project owners feels more connected than replies in issues.
GitHub issues is mechanically better but is (properly) spare in comparison.
Creating an issue, (which occupies a number that can not be taken back), is heavy compared to a chat message.
Discussions are GH’s answer to this but I think those muddy the waters. Having Discussions enabled on only some repos makes them unreliable. And each repo has different criteria for what should go in a discussion.
As much as I avoid Discord, I don’t think the chat based medium is going away. If anything, I could see GH finding a way to enter that fray.