How you ask?
Limited bitcoin supply + fiat collapse.
Next question?
Great, the more the demand of bitcoin, the lower the supply of it and that is what lead to increase in value, he needs to understand the concept, so if he is to do his calculation very well, he would even realize that bitcoin could even reach far more than 100k by that 2021 depending in the rate of adoption and how soon the supply can be reduced and at the same time, the price may still not get to that in tat 2021 which could also take another 5 years if the adoption rate is still low, because it is only adoption that usually cause stir for demand which will then turn to create opportunity for much more surge in the value. All we need to hope for now is not just speculation, but the practicality of it.
If they can influence the market very well, then we will have new investors.