Have a good understanding of the crypto market, study the cryptos and then invest in the potential coins. It is not gambling. Betting doesn’t require knowledge, it is just a mere anticipation.
I guess it's all about the risk that he said about gambling and both has it especially in trading which is higher.
From what I read in the story of what happened to Steven, he did something negligent. I don't know if it happened that he forgot the address where he entered the 5-10 Bitcoins, that's a huge amount even if we say that the price is low at the moment. What is that, he forgot what private key, password, phrase? not clear how lost? because if it is said that he just forgot the address, it means that it is possible that his Bitcoins are not lost, they just can't be opened because he just forgot what address he entered.
If he has already forgotten the private keys then his bitcoins are lost forever and can't be retrieved. But if by some lucky incident and he remembers it.
He can always take it back and import the keys again.