"But why not focus on the underlying idea – if we could make eating and nutrition easier, how? If we could make phones more customisable and modular, how? Where could this lead? The possibilities, once you start thinking along these lines, are endless."
To me, that brudgers discussion does directly and tangentially hint at making things better and benefits of existing solutions. And moreover, some people are good at fine combing ideas and not propose some new. Criticising people because they are being "negative" amounts to living in a bubble.
Btw ironic, considering OP's comments on this article: https://news.ycombinator.com/item?id=6464120