Largest doesn't mean highest quality. JavaScript may well be the most widely used programming language there is. However, this survey is too unrepresentative to give us any evidence one way or the other.

> This is the largest developer survey out there

Generally, having a random sample is more important than having a large sample size. The fact that lots of developers were surveyed means the survey tells us nothing about the language usage of all developers, since they were self-selected on a particular platform.