While attributing “evolution” to him may be a bit of a stretch, I don’t really see that as a Matthew Effect, where more and more fame comes to someone already famous:

In the sociology of science, “Matthew effect” was a term coined by Robert K. Merton to describe how, among other things, eminent scientists will often get more credit than a comparatively unknown researcher, even if their work is similar; it also means that credit will usually be given to researchers who are already famous. For example, a prize will almost always be awarded to the most senior researcher involved in a project, even if all the work was done by a graduate student.

Darwin didn’t discover evolution; Einstein did not derive the equations for special relativity (or those for general, for that matter), but these scientists’ (re-)interpretations of the underlying material — and the subsequent popularity of their results — is what drives the re-attribution. (My guess.)