I've encountered programmers who are not fluent in English (e.g., some of the audience of non-English StackOverflow) but they don't seem to be a curious type (for whatever reason)
They said that there might be because they know people who are interested in the subject but don’t speak English. So I don’t know why you are asking the question.
(Before I get bashed for this, I speak 3 languages well and 4 more poorly, English is my third. It really isn’t a difficult language to learn when all American media and most of computing uses it.)
It is ok that my comment above is downvoted but It would nice to hear any counter arguments (it is hard for me to imagine a passionate programmer who can't learn English).
Language learning is difficult and your success with one language has a lot to do with what you speak natively. I've heard that Italian speakers for instance can pick up English with relative ease compared with someone who grew up speaking Japanese.
People also have different priorities in life. Past high school and university you've got a career and possibly a family to attend to. Finding enough time to learn another language would be a big ask for many.
The link between language learning and curiosity sounds tenuous at best. I would also add that having access to media in a particular language doesn't mean a lot unless you're prepared to put some effort in. I know expats who've lived in Japan for 20 years and can only speak a few words of Japanese despite being surrounded by it everyday.