I would say by a combination of ability and opportunity. Ability in the sense of good hearing and mental pathways that associate easily. Opportunity in being surrounded by a number of different native language speakers. I believe that it is quite common in Europe, Africa and parts of Asia to be polyglots.

to learn to learn and all.

You should give us the link of your video on YT. There is not so much person who are capable to speak so many languages, except if they've been surrounded by different cultures due to their travel or living in other countries since their childhood. Even if you learn 20 languages, you would not be capable to speak every one as fluently as your(s) native (s) one (s). There is at least 5000 words in each, so you can master around 6-7 but it's a great investment in your daily life. You're young, so you've got plenty of time and it's more easy to you than for older. It depends on your motivation, therefore you may manage to catch up with him if only you desire and are ready to invest. But you have to mature beforehand which language you want really master as it takes time and time... That's true also that in some countries, especially in Asia or India, they know at least 2, 3 and even 4 languages and dialects as they're immersed since birth. But there is also some facilities if you decide to learn for instance all the Latin languages which have the same roots. Or if you learn the Chinese, it would be more easy to you for learn the Japanese too. But you've got to think to which one are useful to you and how much you want master each rather to seek to learn a umpteenth. There is no sense in doing a such learning except if you project to use them in an effective way. You can see this video for understand how it's manageable for some : http://www.bbc.co.uk/news/uk-17107435 Work and persistence are determinant.

Hmmmm, at what point does someone stop being a polyglot and start being a hyperpolyglot? This 16 year old sounds like a hyperpolyglot , that is someone who is both a gifted and massive language accumulator. These people possess a particular neurology that’s well-suited for learning languages very quickly and being able to use them. There have been surveys of multilingual communities around the world, and the maximum used in any one community was 5. So ordinary people, who don’t have any special mental gifts can speak 5. Other research shows that many people say they could speak 6 or 7 languages, but they started to fall off at 11.