One serving of Soylent gives me 14g of fat and 13g of protein. Better than a granola bar and some fruit and nuts, which tend to be only carb heavy with some protein.

It's a fine idea and I do eat a lot of nuts. But it's pretty hard to match the convenience and effectiveness of a soylent.

Basically, if you ever have cravings or moodiness due to food, that can be solved by a soylent in about 60 seconds. Maybe nuts can solve it too, but a lot of people don't do that, and end up eating junk instead.