Some people who are only eager to marry a rich person are sometimes considered gold diggers. That's because some ladies may not want to work but only become fully dependent on their husbands, which is not the right thing to do. If perhaps two people are in a relationship and the man just has one source of income, which is his job, while the woman is also working, later, if the man wants to grow wealthy, he can definitely make other investments, and if he is a fan of Bitcoin or crypto, he can also channel some investment into crypto. So apparently, some real marriage did not just happen with the girl being a gold digger, but with both parties starting from somewhere in their small salary income and finally getting married. After they are married, they have more decisions to make, so they decide to invest in other things that could give them a large financial cushion.
Practically, someone who is rich in fiat can also be rich in cryptocurrency if they decide to extend their investment into it. Also, someone who is rich in crypto is already rich in fiat because they can convert their crypto to fiat any time they need the money. For example, imagine someone who has about 100 bitcoins. Because the person is rich, he can convert one or two to fiat if he wants and still have more bitcoins left. If it's someone who is also rich in fiat, let's say $1 billion or more, they can also purchase Bitcoins.
So, back to your question: when you say someone is rich in crypto or fiat, do you have any specific net worth? If not, then I have given you a better example above.
And also, people should marry out of love and not because of money or material things.