Hi,
I think that the most important part of the story of synthesizer, is that the easy way/path was taken to make it sound like everything else we knew. And today, a synthesizer is a threat to replace a band, or orchestra!
I enjoy, and prefer, what they call "analog", which is another word for the fact that someone actually created the sounds and effects for the music they were playing. The keyboard work in many of those early bands, and even Keith, specially in his earlier days, the synthesizer was a different instrument, not a replacement for anything we knew, and that is one of the most spectacular things that was done. Listening to it, made sense to me, as "another instrument".
Some of the experimentations, and the 70's had them by the thousands in Europe, most of them (TODAY!) sound like it was mostly the turning of a knob and fader, but the sentence, or the piece of music had a feeling that was new, and that was fun to listen to! Today, it's difficult to find a band that has keyboards that even try to use them as anything but another instrument in the orchestra! We don't think of Keith, just turning a knob at all ... very different than Neu or Kraftwerk, or Cluster for example.
The sound will last and be used ... but I'm not sure the orchestra replacements will make it ... because if they did they would already be used, and no one across any of the ponds is playing Edgar Froese, Klaus Schulze, Ryuichi Sakamoto, and so many others that deserve the credit and have never really gotten it! Robert Moog, was not a composer, but his sensibility to help create something that DID end up making music, deserves some massive credit, although he was not the only one across the universe doing it.