[atoav]

Tell her to not invest any money that she is not willing to lose.

From what you observed (feel free to cite articles) there are many cases of collapses and scams in crypto — with her being late to the game there is a real risk to lose a lot of money. There is of course also a chance to gain something, but she can't know.

The gist of it is that it is her decision, but that she has to weigh herself how much she is willing to risk to lose. You can only give her information on your perceived state of crypto, the risks involved etc. But in the end she decides. If she just wants risk she could as well just buy a thousand lottery tickets.

If she wants a safe investment this is something else. Crypto is not a safe investment.