The claim of sceptics along these lines is that string theory has produced nothing in 50 years and some string theorists appear to be in denial of that.
In science as in pretty much any other discipline you should always weigh someones opinion by their believability / credibility. The credibility of someones opinion on something is a function of their knowledge / experience of the subject and things related to it. To first approximation most sceptics have close to zero credibility making claims about string theory, as they have not produced scientific output remotely comparable to proponents of string theory. This is simply because people like Witten tower far above most other working theoretical physicists.
This sounds suspiciously like argument from authority. You will be more convincing if you address the argument, not the alleged experience of those making it.
Please see my response to the previous objection in the thread (the sibling comment to yours) requiring specific examples of progress which would silence the critics - it remains unanswered.
Said skeptics are blissfully unaware of the contributions that working on string theory has made to other branches of physics and mathematics. To say it's produced nothing is to admit ignorance.
In the context of this article - physics progression - what specific theoretical discoveries or predictions has it produced that can be verified or disproven via experiment in the forseeable future?
