I just arrived on Sketchfab and it's an exercise in frustration. Someone has scanned some ancient work of art and it's not downloadable. Someone produces a cool model and it's not downloadable. What's the point? If it's not downloadable why do you think ANYONE wants to see it? This site discourages innovation and encourages an "it's mine and nobody else's" mentality...you won't compete with sites like Thingiverse without being open. No wonder your forums are empty.