It's condescending to the people who've noticed they make mistakes and so value a language which is designed accordingly:

"So, put simply, yes, you can shoot yourself in the foot, and the caliber is enormous. But you’re being treated like an adult the whole time"

That is, those of us who've noticed we make mistakes aren't adults we're children and this is a proper grown-up language -- pretty much the definition of condescending.

I can't tell if you're joking or not, but if you aren't, no one is calling you a child. The article is obviously saying that the compiler doesn't stop you from doing dumb things, which is a privilege generally only extended to adults. Nobody is saying anyone who makes mistakes is a child.