Louis, you are definitely playing devil's advocate.!!!

We are currently in a bull market for crypto currency, but going through a bear phase within that. As I said before, the current Bitcoin mining costs are $3,100 and with the halving they will be $6,200. So. if it reaches the latter level, then it will a excellent time to buy.

So, to answer your question - Where is the money going to come from?

It is already there, it's invested in bonds, equities, real estate, commodities, etc. Once these bubbles pop the money moves elsewhere into the next under valued asset.

Think of it as a 'Lava Lamp', the money flows from one asset to another.