Not that it matters even a little bit in this case. It's an irrelevant diversion of the worst kind. It's ignorant and foolish, something for small minds.
It’s just a bad idea to use those light fonts for anything but headlines or other kinds of large type. For the headline that light font is absolutely ok. For the body text it’s just embarrassing (especially since this is from Adobe).
I have to say, though, this blog is written by those at Adobe who develop new standards (for HTML/CSS/JS), so probably very technical people who are more often than not not very knowledgeable about design – that is to say, those involved here do not necessarily have a strong design focus (and neither do they necessarily have to have that).