That's only a prediction but a positive prediction, if that happens then Bitcoin could be worth millions of dollars then, just as predicted by Mcafee but unfortunately, he predicted 2020 anyway, this is the best time to hodl Bitcoin with this figure Bitcoin will be scarce.
I find it difficult to believe that we are going to reach such a huge number so fast, the adoption will have to grow at an incredible speed for that to have any remote chance of happening, I am a little bit more conservative if we could get 100 million people to use bitcoin during the next decade that will still be a big win for bitcoin and it will mean that bitcoin will probably never disappear.