She is building a social network for hobbyist gardeners. Apparently this is what humanity needs more than geek toys like self-driving cars and augmented reality sunglasses.
That's a bizarre critique. It's just more likely she would be working on youtube ad code than self-driving cars or augmented reality sunglasses, which most people would consider less constructive than a social network.
Additionally, I think many people would consider Facebook more valuable than augmented reality sunglasses. If we're going to only build things that humanity "needs", we're going to needlessly limit our scope and put many people out of jobs. After all, our needs are considerably less than our wants.
It isn't a critique. It's about her project Growstuff which she considers more important and valuable than Google's self-driving cars and Project Glass.
"hobbyist" is relative. I started as a hobbyist and eventually expanded it into a business. Also in an era when people are underemployed, I feel that these sort of activities will become a valuable way to obtain a degree of self-sufficiency.