Well, it is a surprisingly natural path from Quantum Field Theory (QFT). So many things we get for free (primarily: gravitation), I would be surprised if it were just a random coincidence.

Yet, no one knows how to turn it into an actual theory in physics. It feels like we had QFT but weren't able to create the Standard Model.

It is, obviously, possible that the String Theory framework is just too broad. Or that it is in principle true, but we reached a level where it is too hard. Or it is just a step in the right direction, but we are missing something.

Given the effort of the smartest minds and still no progress (I do not think there is any hype left), it is possible that we need to wait for something more. Like the revival of artificial neural networks in the 2010s, after decades of slumber.