This is my most painful memory. In 2011, my brother asked me to borrow money to buy a computer to mine bitcoins. I searched online for what bitcoin was and it said it was a scam. Then I turned my brother down, he was young and he couldn't carry out without my funds. The second time I heard about bitcoin was in 2019 when my boss introduced me to bitcoin again.
Didn't your brother argue you on why you said it was scam? He should have show you proofs that it was truly legit. This is why it's also important to listen on others and not just ignore them easily thinking that they are wrong and we are always right.
It was amazing that at his young age he is already interested on those things while many young people do only have an interest in video games and other things who are not really that beneficial for them. I think on that time, I was still a fresh graduate from highschool and I am only relaxing, and sometimes playing. I only heard bitcoins I think on 2014-2015 but I didn't got involved with it immediately. I dont know why so I also have a regret.