Talking about things like solving the Reimman hypothesis in so many years assumes a little too much about the difficulty of problems that we can't even begin to conceive of a solution for. A better question is what can happen when everybody has access to above average reasoning. Our society is structured around avoiding confronting people with difficult questions, except when they are intended to get the answer wrong.
What does this have to do with a hypothetical automatic theorem prover?
If you want a computer to be able to tell that it found a correct proof once it enumerates it, you need a bit more than that (really just the existence of automated proof checkers is enough for that).
Hilbert’s program was a (failed) attempt to determine, loosely speaking, whether there was a process or procedure that could discover all mathematical truths. Any theorem depends on the formal system you start with, but the deeper implicit question is: where do the axioms come from and can we discover all of them (answer: “unknown” and “no”)?
Hilbert's program failed in no contradiction to what GP wrote because the language of FOL theorems is only recursively enumerable and not decidable. It's obvious that something is true if you've found a proof, but if you haven't found a proof yet, is the theorem wrong or do you simply have to wait a little longer?