If you choose the broader definition, then al-Qarawiyyin clearly qualifies very early. If you choose the narrower juridical definition, then historians debate whether the madrasa structure fits that category prior to modern reforms.
In short, it’s not a university. And that’s okay. Trying to pigeonhole it into that definition is the issue.
"If it's the broader definition, it's a university. If it's the narrow definition, it's debatable. In short, it's not a university."
You legitimately don't see it, do you.