Git-adjacent issue trackers are communication tools for developers. JIRA is a surveillance and control mechanism for senior executives. It just depends on the size of your company.

How do you deal with projects that have multiple Git repositories associated with them, but need to have their issues tracked in a single place?

We were fine with just using Github Issues... until we weren't. At a certain scale, it's too hard to sort and filter issues and since you can't add fields it was hard to capture all the issue metadata we wanted.

Lab enterprise, yeah. They are utterly useful in our case since we are working on a branch per issue model, which makes it extremely easy for tracking and code reviews.

GitLab includes kanban boards, actually.