> If the critics of string theory could prove it was wrong, they would have, but they haven't yet. That makes it provisionally correct.
No, absolutely not. This is the kind of argument an amateur apologist would make for the existence of God. You need to think about what "unfalsifiable" means and why it's a pejorative term in science.
There are tons of tests that would falsify string theory. Demonstrate, for example, that it's not possible to calculate the observed mass of the electron, and you would falsify it.
