I read Lee Smolin's book on this debate (The Trouble with Physics). I think what happened in theoretical physics -- to the extent that it's spinning its wheels

I read Lee Smolin's book on this debate (The Trouble with Physics). I think what happened in theoretical physics -- to the extent that it's spinning its wheels with untestable theories -- is largely that there are too many theoretical physicists and not enough hard experimental data to chase after. When there is nothing much interesting happening in a field, it's always going to be tempting to point the finger at whatever annoys you. But if there were important discoveries to be made, probably string theory would not prevent someone from making them.