I believe museums in general will always have personality issues to do with. Even without that, many museums (railroad, historical, etc.) are seeing shrinking attendance and membership. Look at the NRHS as a whole and they're also shrinking for a number of reasons.

Our railroad park in Medford, Oregon has five different railroad clubs that together operate the park. A couple are doing well, while others are shrinking. We're always going the extra step in being creative and offering extras to the public. It is working, but it won't work for all clubs as railroads as a hobby is fighting for the hobby dollar with electronic games and other attractions which were never thought of decades ago.

You need to be creative and adaptable (within reason) to attract customers. Private business has to do it. If they fail, they go under.