Also, I have always been impressed by how well those in countries where English is not a primary language can speak English.
English was mandatory in most private schools where I lived. Granted, that doesn't mean you'll end up being fluent in English (in fact some of my friends sucked at it so much they can barely understand the word "Hello") but if you put a little effort into it you could become pretty decent at it.
I think that public school proficiency in Spanish schools is probably worse than that of the private ones.
"In theory" students are meant to leave high school with an A2 level of English, and if you go and finish a university degree, you need to have a B1 level of English.
Then again:
1) A2 and B1 aren't exactly great levels of English, especially A2. B1 is a lot better though, but I think you don't get fluent until B2? (which is very good English and perfectly acceptable for most purposes)
2) For at least the college degree part, most of the time there is an "english" class that allows you to skip said requirement and is ridiculously easy.
3) If you do not practice a language regularly, you will eventually forget much of it. I know this first hand as it has happened with my German (which I used to speak a lot better back in the day). And the only reason this has not happened with my English may ironically be Atlas and other such forums
That also doesn't mean that all or even most public school students do not speak English; many actually do speak English fairly well; but there is also plenty of young people who do not speak English very well.
English-speaking parts of the internet with non-native parts tend to be an extremely unrepresentative sample of said countries.