The idea of 'Black Holes' is still just a theory, it's a largely accepted theory in science today, however there are some legitimate and objective arguments against its validity. There is still much we don't know, and while black holes may provide a model for further investigation, our understanding of the workings of the universe and reality are open-ended questions, and perhaps always will be...

"An American physicist claims she has mathematically refuted the existence of black holes in our universe. The new theory combines Steve Hawking's radiation theory with quantum theory’s fundamental law that no information ever disappears from the universe.

Professor Laura Mersini-Houghton from the University of North Carolina at Chapel Hill maintains she managed to merge two seemingly contradicting theories, Einstein's theory of gravity and a fundamental law of quantum theory." - https://www.rt.com/news/190540-black-holes-are-nonexistent/