You wanna know the real reason?

0 - printers doing brrrr buing treasury bonds
1- this makes negative real yields on bonds (this push money down)
2- interest on term deposits in banks are close to zero (this push money down)
3- corporate bonds risk of not being paid is bigger than expected ROI (this push money down)
4- inflation and fear of inflation getting bigger and bigger forces people to look for assets that will protect their funds from inflation by accepting even greater and greater risk (because safe assets guarantee a real loss (expected profit - inflation))
5- this push money to real estate makes them super expensive (3-4 % from renting is still not enough to cover inflation)
6- this push money to deeper and deeper (stocks and dividend profits) but they are cosmically overvalued and dividends are very small
7- this push money deeper into high risk assets (bitcoin)

This pump is not caused by Paypal or halving. It is caused by panicked investors searching for good place to hide from inflation.

“The United States printed more money in June than in the first two centuries after its founding,” Morehead wrote. “Last month the U.S. budget deficit — $864 billion — was larger than the total debt incurred from 1776 through the end of 1979.”
https://cointelegraph.com/news/us-printed-more-money-in-one-month-than-in-two-centuries

"In response to the coronavirus, the Federal Reserve has printed approximately $3 trillion. The total assets of the Federal Reserve as of the end of February 2020 was $4.16 trillion. By the end of July, total assets was $6.95 trillion."
https://medium.com/discourse/do-you-realize-the-massive-amount-of-money-printing-happening-due-to-the-coronavirus-pandemic-1f4347cc0404