Any time things go to infinity in physics, we know we haven't gotten it right.
Gravity wins over all other known forces.
As an astronomer, I get to ignore the details of the things that we dont understand. Theres a lot of work that we can do on scales that we do understand, and there is actually a finite size that I can associate with a super massive black hole.
Black holes are very exotic objects. Technically, a black hole puts a huge amount of mass inside of zero volume. So our understanding of the center of black holes doesn't make sense, which is a big clue to physicists that we don't have our physics quite right.
The Keck telescope, which is the largest in the world, had opened just before I began my faculty position at UCLA.