Quantum mechanics, is not "just one thing", so to say "it is true" is somewhat wrong I think.

You are probably talking about the Copenhagen interpretation, involving superposition.

Personally, I don't think this is the final theory.

Any theory using calculus, cannot be considered discrete, so is therefore not quantized, and not possibly "physical".

Gerard 't Hooft has more to say on this if you want to hear something from a nobel laureate on the subject.

Yes, agree that suggesting "true" is unclear, and in fact in science doesn't really talk about true things but rather than ability to predict the way things behave. We are still in the dark about the fundamental nature of reality. Science is still useful of course, but only insofar as it has a useful purpose. It's more like an engineering subject.

I think what I've just said foots with your calculus comment, and also a Wolfram-like interpretation is closer to "truth" and your point on discretisation.

Why do you think discretisation/quantisation is necessary for the "physical"?

What can I search for to find his comments on this subject?