Those are text-only and don't support comments, labels, statuses, markdown or basically any of the other things that might make issues useable.
There are issues that apply to a whole org. There are "non business people" that know how to add context to an issue but not exactly in which repo it might fit best.
"Notes on a board" is not a replacement for org-level issues.
We encountered the same issue, but it seems to be only for projects at user/organization level. What we do to work around this is to create a new repository used solely for projects.
By doing so, you can create and put the issues in the project board, and apply labels to the issue (which does show up in the project board). The long details can be put in the issue description, and it can be linked to other repositories nicely as well. The trick really seems to be to not use user/organization project, but (dedicated) repository project.
I wish they documented this better or improve it somehow, but hey! I guess they were working on the beta issues board/table which is also pretty sweet!
There are issues that apply to a whole org. There are "non business people" that know how to add context to an issue but not exactly in which repo it might fit best.
"Notes on a board" is not a replacement for org-level issues.