I can answer for myself. I speculate that a transition from fiat to crypto is inevitable unless a black swan event occurs. (Eg a new way to represent value is invented that is superior to fiat and crypto that is currently inconceivable today)
If the transition to crypto does occur, it clearly benefits early adopters. In late phases of the transition, there will be very few people willing to trade crypto for fiat.
Herein lies ammo for the crowd shouting “CRYPTO IS A PONZI”. But the truth is that all desirable possessions are this way. If you bought beach-front property in a great city decades ago, you’re going to be able to sell it to the next “sucker” for a huge profit. Likewise, Apple stock. Likewise, a baseball rookie card. Etcetc
> Okay, but how massive?
This is a difficult question. It depends on if the transition is a gradual, long term grind. Or if some event occurs that shocks the system and causes a mad rush to cryptocurrencies. I hope for the former and fear for the latter.