I know I will get downvoted for this as off topic, but this is just the latest blog we've seen in this top 30 of many that show ZERO regard for legibility. Yes, I can zoom my browser, but c'mon. A 13px font for paragraph text is nearly hostile. It's not that legible to people with perfect eyesight, but then it's not at all legible to anyone with imperfect eyesight. It's like saying you don't care if anyone who reads…
Firefox even lets you set a minimum font size. And there is an option to stop websites overriding your choices which helps with sites like HN (but not the one you are complaining about) which explicitly set a small font size.