You're not wrong, but what you're not appreciating is that the criteria for "pretty and elegant" are the same for string theory, the standard model, general relativity, and any other physical theory: a relatively simple and internally consistent mathematical framework that, when carried through in calculations, produces predictions that match a wide variety of observations, and is not contradicted by any known observations.

Proponents of string theory have not been able to propose an experiment that would allow them to exclude other theories, thereby demonstrating that string theory is better. But by the exact same token, critics of string theory have not been able to conduct an experiment that contradicts string theory, thereby allowing them to exclude it. And science moves forward by excluding theories with evidence (not just complaining about them).

Discussions of string theory among physicists are deeply intertwined with concerns about who gets famous, who gets grants, who gets tenure, who gets endowed chairs, who gets on TV and sells books, etc. But these types of concerns are a constant background noise to the practice of science, going back hundreds of years. Every scientist on Earth tends a private list of the wrong people who are getting too many resources to study the wrong thing.

If the critics of string theory could prove it was wrong, they would have, but they haven't yet. That makes it provisionally correct. Not correct, necessarily--it could be wrong! But it's not wrong yet, which is better than quite a lot of scientific theories proposed across the span of history (for now...).