Doesn't Ensure provide these same options? If so, is it fair to really call it a revolution, or it is just providing something like Ensure at a lower price point?
From what I can tell, Ensure is pretty much the same thing. I certainly don't consider Soylent to be a revolution, beyond perhaps a marketing revolution in the tech community.
Ensure does provide an option, but it's relatively expensive, lacking the full range of nutrients found in Soylent, and pretty high in sugar (though I think they have just reduced sugar slightly).
I fed my brother Ensure through a tube in his nose for 2 months before an intestinal surgery. The doctors considered it as good of a meal replacement as any for that amount of time.