I think those people that holds their money in fiat and saves it for the best use that they can are aware of the inflation that lessens the purchasing power of their fiat. But, we don't know if they have some plans of spending it to any asset that they have in their minds. For them, they know that cash is king and that's why they are keepin as much stack in cash that they can. Because if they want to purchase some stocks or even crypto, they have fiat ready for it to be done. There's so much that they can do with it but for me, I like to have balanced portfolio. Have some cash and crypto too.
No matter any future plans that anybody has for their money, considering the way inflation is hitting hard on the Fiat now, it will not be wise to stack a lot of money in Fiats because no value will be added in the long run. However, keeping a balance between Fiats and Crypto is a good idea but for me i would like to keep most of my money in bitcoins, like about 3/4 of my money while the remaining part will be in Fiats for urgent needs and getting some stuffs but since i have known the potential value of the amount i kept in bitcoins, it will remain there in the long run.