Living in shadows
No, I do not think so.
It is human nature to theorize the unknown, with the hope of solving the mystery hidden within. Geoffrey of Monmouth was no different. His Historia Regum Britanniae recounted a legend involving Stonehenge. In the absence of a better explanation his legend was accepted as a plausible reason for the structures existence.
However, move onto the nineteenth century, and Geoffrey of Monmouths legend becomes fiction. As archaeology evolved from the antiquarians to the modern precise science of today, so have the theories by removing the fiction from the fact.
Our modern day archaeologist deals with facts. We know the when, we are getting closer to the how, but we are all still speculating the why. Speculating being the obvious word here. No legend to be seen.
Sorry Geoffrey of Monmouth, I am fairly sure there was no Merlin involved.