We can argue about whether string theory really simplifies things later, the point is the focus on the mathematical solution being "elegant" ...
You might be giving too much importance to "elegant" here. It can often happen that the same ideas can be formulated in two (or more) different ways, one elegant and the other ineligent. Mathematicians tend to prefer the elegant version. But the difference is only in the way things are formulated. If used to describe reality, both would describe the same reality.
The issue is whether the math - particularly the 'elegant' solution - is considered more important than the evidence (or the lack of evidence).
You are probably looking at this from the vantage point of biology. There are good reasons why physics is different. For one thing, physics deals with fundamental concepts that are eventually used in other science. The mathematical formulation is often needed before you can even decide how to start collecting the evidence.
It is my impression that physicists are concerned with evidence. They consider their mathematical theories as speculative, until enough evidence has been acquired to support them. It is my understanding that string theory is still considered speculative.
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