So the article loses credibility almost straight away:
Lucky Einstein didn't publish the theory until 1915 then.
I asked the author about this and he claims that it was a typo which I pointed out didn't really make sense in context as he said it should be 1919 but he stuck to it being a typo. (Note I think Eddington planned an earlier test in 1919 but haven't verified this) That there is an error such as this doesn't reall mean that the whole credibility of the article falls and most of the commentary after in terms of the current delineations in what makes something science is fairly well known.
As regards String Theory, I think the ruckus about it is a storm in a teacup dreamed up by philosophers trying to keep themselves in work. Richard Feynman said this:
https://www.youtube.com/watch?v=EYPapE-3FRw
String Theory is somewhere between the guess stage and the computing the consequences stage. Eventually, either somebody will find a way to falsify it and it will stand or fall on experimental results or somebody will find an alternative that can be falsified or at least shows more promise and everybody will forget about it.
I doubt there are that many philosphers kept in wok by this and much of the dispute as is clear in the article is rasied by the scientists rasising the hypothesis. Note the article effectively agrees with the point that Feynman made and points out that this progress to verification isn't necessarily against Popper's position.
I think the issue is one that is is more psychological than philosophical in that the attempts by some scientists to talk of a non empirical science is merely to cover up their lack of comfort at not currently knowing any ways of falsification. Once upon a time that sort of speculation and hypotheising would have been seen to be fine and perfectly scientific but Popper's attempts at addressing the demarcation problem have become ingrained so that without the falsigication people feel worried that it isn't science. That a process might be stretched out seems to me to not rule out falsification.
I sense that some of this discomfort comes as we see science in the light of disputes with religion - I can see no reason why Carroll debated WLC for example.