I still remember the year 2015, during my National Youth Service Corps (NYSC) in the east part of the country. One of my fellow corps members caught up in the craze of the Ponzi scheme era, sold all his Bitcoin just to invest in one of those schemes. I recall him even offering to sell me some of his Bitcoin in exchange for cash but I refused.
Looking back now the past is truly behind us. We should have invested in Bitcoin instead of falling for Ponzi schemes. The value we overlooked then has now become a lesson for the future.
We all learn differently in the crypto space, and some people learned from previous experiences, so it should be a lesson for you and your guy. The price of Bitcoin was very cheap in 2015, and not everyone was aware of its worth or how much it would be at this point. Even some members of this forum will not buy Bitcoin at that time because not everyone believes it and we cannot predict how amazing it will become in the future.
However, knowledge is very important. Your friend learned the hard way due to his greed, and he ended up selling his Bitcoin because of some criminals. Perhaps someone advised him to sell his Bitcoin and invest in a project to give him more profit. To be honest, if he looked at the Bitcoin he was holding back then and compared it to today's rate, he would realize he had made a big mistake in his life. And that is not the goal right now, he should learn from it and start investing.