I am also unsure of whether he meant that it should be eaten directly. On the assumption that this was part of the vision, I associated the paste with those little tube things for toddlers. I’ve seen a lot more of those kind of products, and I assumed that he was referring to a Soylent-based version of something like that. If so, it would be perfect for backpacking as long as it came pre-flavored.
Nothing that they have made has yet come pre-flavored in the ordinary sense of the term, and I’ve liked the freedom it gives us to tailor the product to our own tastes. But with either a paste or a solid bar, that wouldn’t be an option, so having a range of flavor options would be critical.
On the other hand, if @JeffLeBert is right and it was floated as an idea to lower the costs of shipping then we’re having a new conversation. That would allow for the flavoring to be added afterwards again, and it would lower shipping costs, hence, over time, price. For these reasons, it would also be excellent for backpacking although it would still have a major bulk issue.
Please note that my thinking here is strictly centered around the advantages a paste would provide for backpacking. Soylent is potentially the perfect product for backpacking. In other situations, I don’t see much reason for the paste.