You are 100% correct. It turns out that I am an OK engineer, and a terrible marketer. There is a LOT that I need to improve on the site and the videos.
Every one of those pretty-looking screenshots should have a play button with a few seconds of audio. It's really strange to market a synthesiser with visuals instead of sound.
Yes, it's a synthesizer -- you may know it inside and out, but having demo videos showing what it can do will help people with no context get that quick "ahhh, that makes sense" moment from things. :)