Your friend is lucky. If he invested in altcoins, maybe that could be the altcoins era that is the time before 2017 when the rally for altcoins was very high. Coins like etheruem at that time were very cheap and ico scam was not that rampant.
Maybe he was part of those who bought bitcoin early like 8 -10 years ago when the price was still below $1k. He is worthy of commending if he actually saw the future from the risk he took because some people saw the opportunity but felt cryptocurrency investment was all fraud.
If he invested in bitcoin 8-10 years ago, then this is a very good decision, as we can see today. But maybe then he should have sold them at the highest price a couple of years ago. Perhaps he, like many people, was waiting for bitcoin to increase in price even more and missed the moment to successfully sell it, then he is most likely now worried about this