Valve has always been known to be hands-off and let the community create their own content. They are vocal about a hands-off process, one which can eventually make sure that the community does not feel stifled with the intervention. Ofcourse it does not always work out for the best and recently there have been calls for the game developer to be more involved.
https://twitter.com/Mapcore/status/948909941313736704/
Valve will now be contributing to the prizes of the Top four finishes at the Mapcore contest. The Mapcore contest is a contest for upcoming talent to prepare and develop maps.