I think that realistically millennial should stretch as far back as 1990. Because nothing of real significance happened in the mid/late 90's (or at least, nothing they told me about) the realisation about world events and such started with 9/11 for that generation. We also shared in the Harry Potter boom. Heck, I can remember waiting for the release of 2 and 3 - these were the books that literally taught me how to read.

At any rate, if you look at the popularity of competitive and violent video games then you know that the spirit of competition/violence is far from dead and that in fact if anything was to pose a risk to football it would probably be these acting as competition and drawing kids away.

Not that any sports fan would ever admit that their passion is no longer the best way to get kids fired up, excited and entertained

(OTOH, I live in Australia and sports are obviously far from dead here. Well, maybe Rugby League.)