Indian languages are also pretty similar by regions. I spent 10 years in Bombay which made my Hindi really good. This also meant that I kinda know and can understand quite a bit of Marathi and Gujarathi. As I'm fluent in Hindi, I can also understand most people in the north and center speaking Hindi-esque languages too.
We are in the south for the past 6+ years, and I can begin to understand Kannada for the most common words.
Here is a personal fun-fact. I'm from the northeast and we have the "Asian" look and not the typical Indian. Most of the times, I default/pretend to not knowing Hindi unless communicated to. Lots of fun when people talk around me; assuming I would not understand them. More fun - when I'm outside India and Indians talk shit, defamatory, derogatory, embarrassing, things about other people and about themselves in Hindi - I always pretend I don't understand them at all.
Why is that?
Now to our kids' generation, most of whom are raised outside of the region. And thanks to the intermingling marriages, it is even worst. Just in our family, our kids' cousins are Americans, Marathis, Biharis, Khasis, Tankhuls, Nagas, et al. I'm still discovering more and list will sure increase. Not just communities, our extended family is an amalgamation of Athiest, Hindus, Muslims, Christians, and what not.
Sometimes, during fateful summer vacations or a big family ceremony, when all the kids play come together, their common language is — you guessed it — English. They all talk a blend of many but English remains the de facto that everyone can communicate.
Actually I'm not just being a smart-ass here, I do have a point. The major reason that so many Americans are monolingual is that learning a second language doesn't have much if any day-to-day utility, whereas in India a second or even a third language may have tremendous day-to-day utility.
But on the individual level, being an english speaker can make it harder. I'm living in Norway. I've had a couple years of immersive language classes. Most of the population speaks English, and many assume to simply use that when speaking to me. The accent and all. Some Norwegians don't see the point of an english speaker learning the language here. A fair amount of the popular music is in English, even Norwegian bands. Television? Childrens tv is dubbed, but a lot of adult television is English with subtitles. Advertisements? half and half. Telemarketers? Often english speaking.
Some books never get translated. Right now, I'm shopping around for a Norwegian copy of The Hitchhiker's Guide. Luckily it is available in Norwegian: Unluckily, it doesn't translate as well so it is a little different. And I'll probably have to order it. The local comic store, where I would normally buy sci-fi or fantasy, mostly sells English books.
Yet for all this, I'm highly motivated. It is really hard to be a part of normal society without Norwegian because this is what folks use in their everyday life. Not everyone here is strong in English, especially older folks. Some workplaces are in English, especially in the tech field, but many aren't. I'm not in the tech field, so learning it is. I'm getting there slowly :)
It's not like English is the only useful language.
True, but in most of the U.S. the number two language isn't all that useful. Also I should add it's not just a matter of utility, it's also a matter of opportunity. I mean sure, if you go looking for speakers of another language you can find them, but it's not ambient. I hear many different languages spoken here in Seattle, but almost all of these speakers speak English well.
Also I should add that I'm not arguing against bilingualism, I'm just saying there are practical reasons why it is not so common here in the U.S.
Even in tourist-soaked countries like France, good luck speaking anything but French out in the boondocks.
Down south Hindi is less prevelant but 2 languages is like the norm for kids here..