At the first period of crypto market development Bitcoin expanded immensely. The scale of its occupation is really hard to imagine. Now it is really difficult for any other currency to reach the same level of popularity.
Well, yes, such a success will be very difficult to repeat, even while it looks unrealistic
It's succes over 3 years of time might be harder to repeat, because there are far more good coins on the market nowadays.
But by the end of next year, I suspect the succes of Bitcoin will start to fade. The technology behind the coin isn't what the cryptomarket needs.