So I guess dark matter does not exist either, because it also is invisible?

The problem here is that you are applying everyday experience to a situation that manifests outside of everyday experience. The Universe is not Euclidean. It is now known that gravitation arises from the concentration of quantum information. (Look up "ER = EPR") If that sounds confusing, it is because things do not operate in the simple way that Newton imagined. Euclidean space and Newtonian mechanics are only valid within a narrow range - the range that we can experience as very delicate organic life forms. At the immense extremes of energy that occur throughout the universe, things are not Euclidean.

Theoretical physicists are not "clowns" as you call them. Theoretical physicists derived General Relativity, which _has_ been proven. And Quantum Mechanics, which _has_ been proven. And the Standard Model, which _has_ been proven. And all of those predicts things that we cannot observe through "everyday experience".

Instead of making conclusions about things without having the theoretical training and then calling physicists - who usually have IQs in the 99th percentile - "clowns", it would be more sensible to read about these things and have wonder about them. The Universe is amazing. Physicists do not fully understand it - in fact, it appears there is a vast amount that we cannot see. But physicists are not clowns. And a Newtonian view will not tell us what is inside a black hole.