It isn't to late to buy Bitcoin until the last block is mined.
Why does the last block gain so much importance from your perspective? Of course it might end up being an event in the community but it is far off and by the time that happens the price could have already gone up beyond the common man's reach to be anything significant. That leads us to the one problem, the rising cost of buying bitcoins even fractions is too much for some people.
Maybe Bitcoin isn't able to make you a billionaire in 11 years from now but it's still a good investment.
One should not dream of becoming a millionaire but dream of becoming successful in life, money will follow success. Hence my advice is to buy small amounts of bitcoin on every drop, focus on what you are doing in real life as well. Who knows one fine day you might have bitcoins worth a lot of money and still having a stable day job to rely on.