Earlier quoted context omitted.
When I had crypto assets, I came upon this article about “Greater fool theory” https://en.wikipedia.org/wiki/Greater_fool_theory It made me sell all my crypto (luckily at a profit), and I have not looked back.
So you basically don't invest in anything because that theory can be applied to any asset.
In general, anything that turns a raw material of some sort into a more refined product (be it iron ore into steel, steel into machines, or electrons into advertisements) is adding economic value into the system. By doing that work, the total net wealth of humanity increases. The economy is positive-sum, and so investing in anything that's correlated with the economy as a whole should be worthwhile.
Bitcoin doesn't work that way. Trading Bitcoin isn't adding to the total net worth of humanity. Mining Bitcoin arguably could be, because the ability to make transactions has some value, but the practical value of those transactions is less than the value of the electricity, computer hardware, and pollution that go into making them. Speculating on Bitcoin does nothing productive; it's zero sum. Net-zero systems are nearly indistinguishable from gambling unless you have insider information.