Doesn’t “serve” really mean lead services?

“Serve” means just that, not “lead”. It means to give of oneself in some capacity to other members of the Minyan and/or to the Minyan as an entity. Important as it is to lead or coordinate aspects of services, these represent only the most visible modes of service. Other ways to serve include participating early and often in our services, helping create social or educational activities by joining one or more committees, and attending shiva minyanim.