I forgot to note one more thing:

> And other languages like D and Go are too new to bet my work on.

Java, the author's favorite, is 26 years old. D is 20 years old. I'm not quire what exactly makes the six year difference so important here. (Sure, Go is 12 years old, that probably classifies as way younger.)

Well, one of them is known by 8 million people, the other by like a couple thousands?

(But don’t get me wrong, D is a cool language, but it didn’t get as popular, so smaller ecosystem, developer mindshare will weaken it’s position)

The author likely meant that D comes with fewer batteries included and a less mature/less numerous community of developers, not that it's literally younger.