I felt exactly the same way. In its most generous form, the rant boils down to "well... if you know Javascript well enough, you could dispense with things like .indexOf because you could implement it yourself!" It's quite low-effort, and I don't understand how it's made its way to the front page.

I'm guessing there are lot of folks who have all sorts of frustrations with React (as there will be with any tool/service that is used by that many people), but this article is 100% devoid of any actual criticism of it, constructive or otherwise.