The blog post is full of great one-liners, like "Surely our minds can find more enjoyable activities than chewing." The guy comes across as very earnest and attempting to be rational about his invention, which is a welcome departure from your usual fad diet pusher.
That said, the OP is unduly optimistic and uncritical. The odds of a dietary breakthrough of this magnitude being missed by the meal-replacement manufacturers are not high, though it is, of course possible.
I like chewing. I would like something like soylent, but in a form I can actually eat.
Rob Rhinehart's food replacement Soylent now has a crowdfunding campaign.
If you're interested in one or more of these benefits, send in some money! There is also a new blog post.