I mean age does not really matters, that money to invest and knowledge about it are what that really matters. Although, I understand what you are trying to point out there but which is correct. People above 45 have achieved and got fixated to what makes them make money and not want to try new one.
What that also matter is how the person that is convincing them to buy bitcoin is. If the person makes huge fortune from crypto investment, they can be interested. I mean above 45 people.
No matter how good your skills in marketing are, you have a better chance of convincing young people with no money to take out a loan and subscribe to a new monetary technology (Bitcoin) than you do of convincing a Luddite with money to buy one.
They have a belief system and it's difficult to start something New.