I guess it is fair to assume that the bitcoin has become a extra-money sponge that absorbs the extra money floating in the market right now. When there will be

I guess it is fair to assume that the bitcoin has become a extra-money sponge that absorbs the extra money floating in the market right now. When there will be less and less "free or cheap money floating" people want to get their money back from the investments they made and this is the exact point where the burst occurs. It would be no problem if the decrease is happening at the same speed as the one of the initial increase, but due to human emotion, the decrease is happening orders of magnitude faster than the increase. At that point, the money will magically disappear. It's a natural process that balances the value of the money available in the market. One interesting point to note here is that the value of the entire bitcoin monetary mass is about 0.25 trillion dollars. That's something like 1% of the whole US national debt.