Think of Tulip Mania in the 17th century. Then think about what happened when the tulip “holders” discovered there were other flowers in the world.
There are times of irrational exuberance in the stock markets periodically. I've managed money through them.
The current run up in crypto "feels" to me like the run up of stocks in 1998-2000.
People bid up the prices - particularly of internet companies - to unrealistic levels.
Eventually, we learned how high "up" is and the market corrected.
If I remember correctly, Amazon dropped 90%.
Eventually, the internet became mainstream and today Amazon is one of the largest companies in the world.
But of course, to your comment, tulips had little intrinsic value and it was short-lived.
Time will tell.
But my own take is that the Blockchain is transforming business already and will continue. That is why I'm involved.
Large companies like Tesla are buying huge quantities of Bitcoin using them for commerce. I don’t believe this is a fad.