The author seems to have the numbers straight in terms of personnel costs required to run a sustainable business, but what's confusing to me is that this analysis was not run before they decided to start this business. It seems like the numbers were hopelessly unfavorable pretty much any way you cut them. To me, that says that there simply wasn't a business worth creating.
I acknowledge that the problems outlined in this piece are real. The commentary about the SF healthcare plan only being available within the city limits when many of its beneficiaries live far away calls attention to how badly dysfunctional our healthcare system is. Nevertheless, I keep coming back to the conclusion that most of the hardship (on behalf of the author) here was self inflicted. Running a restaurant is generally a very poor means of making a living as the author repeatedly points out. It's great that this person was following their passion, but doing so is usually expensive.
As a mental exercise to the outraged reader of this article, try substituting the word restaurant with the word yacht and all the positions with various nautical ones. I think you'll find yourself a lot less sympathetic. I'd argue that they're semantically identical in this case.