Curious you drop the adjective "overwhelming" in your quote and confuse scientific theory with hypothesis.

https://en.wikipedia.org/wiki/Theory "In modern science, the term "theory" refers to scientific theories, a well-confirmed type of explanation of nature, made in a way consistent with scientific method, and fulfilling the criteria required by modern science. Such theories are described in such a way that any scientist in the field is in a position to understand and either provide empirical support ("verify") or empirically contradict ("falsify") it. Scientific theories are the most reliable, rigorous, and comprehensive form of scientific knowledge, in contrast to more common uses of the word "theory" that imply that something is unproven or speculative (which is better characterized by the word 'hypothesis')."

Seems like a fair point to me. If science is really about reproducibility, then this is a fair question. How can we say with absolute certainty until we run a falsifiable experiment?

Note that I'm not disputing our understanding of how stars work. The point is whether our understanding is based on reproducibility.

With that definition of fact, very very few facts actually exist at all.