This is because of current prices. Even the current price point is a good time to entry. Anyone holding one bitcoin can make about $100000 in profit in next year at current prices and past growth.
We're certain and hoping that $100k is going to happen soon but not everyone can avail to have 1 Bitcoin and those that have it, well, we're just waiting for the right time until it comes.
And this milestone will not stop and it will more astonishing in the near future when everyone starts to see how much bitcoin is once again.
No other investment will give these returns.
Well, those that have made a lot of profits with altcoins can argue with you. But of course, we're forever with and for Bitcoin.