If evidence is found supporting string theory, will it change the way we understand the world dramatically?

Answer 1

Your question is premature by years or decades. There still isn't a string theory, there are just many works in progress. Even if a satisfactory one is found, we do not yet know whether it will be just a useful mathematical construct, or whether it will reveal deep and fundamental knowledge about the nature of the universe.

Answer 2

11 dimensional string theory, (and 26 dimensional M theory), has not produced anything.

It is possible that the extra 7 dimensions of space in string theory, (that are not perceived), are mathematical deception that first appeared with 5 dimensional Kaluza-Klein Theory.

String theory is possibly deception involving adding dimensions of space to the already existing 3 dimensions of space one dimension at a time at 90 degree angles to the previous dimension.

That string theory is possibly invalid is stated at the end of the wikipedia article on string theory.