Their product is essentially slimfast without added flavoring and they've demonstrated themselves deficient in procurement and supply chain management by constantly delaying shipments.
Why is that company valued so highly? What makes them different from any other meal replacement shake vendor?
Well, that's a good thing, certainly better than the opposite.
>What makes them different from any other meal replacement shake vendor?
IMO, a focus on being a food replacement rather than a meal replacement.
A food replacement needs to have all your nutrition in one product. They don't care about taste.
Slimfast, as you suggested as a comparison, isn't meant as a 2,100 calorie/day food replacement. You'd have to drink ten 11oz cans to get that many calories and that would throw off the entire ratio of fat, carbs, protein, and nutrients per day.
In any case, soylent seems to have the right product/market fit.