Yeah, I can imagine people do not like the separation. But I also agree it makes sense. If you some of the discussions on issues, esp. when dealing with larger chunks of functionality or controversial features. These issues remain open, and hence ‘on the backlog’ eternally. And that may affect the workflow (or even how people perceive the project, e.g. such as those with thousands of open issues). Issues and Discussions have different commenting UI also, where the latter is threaded.