For investment, one of the factors that influences differences in opinion is the year he/she is born. Let's say he was born in 1980 and was in his 20s in 2000. In 2001, the Dot Com bubble (recession) occurred, and many people lost a lot of money due to investments. Therefore, to him, investment is seen as bad and risky. The risk is not worth taking.
On the other hand, if he was born in the 2000s and in the year 2022 he was 22, a recession happened due to Covid. Stocks declined tremendously, but afterwards, most stocks reached new all-time highs. For this person, they see investment as a means to increase their wealth and believe it's worth taking the risk.
In short, our parents lived in different eras and learned different life lessons regarding investment or any other domain. I agree that their advice is worth considering but cannot be wholly relied upon. Ultimately, we are the ones who execute our decisions.