Have you tried something similar?, maybe now thinking about doing it?, I think it's a great idea.
I have always been interested in doing something similar, investing a portion of what I earn in Bitcoin every month without touching it until Bitcoin goes pretty high so that I can use the money to start some business of my own and manage and grow that for the rest of my life. Unfortunately, I have never had a source of income stable enough to allow me to achieve that because to do something like that, you must be earning more than what you need based on your expenses.
He started pretty early, which is a better thing because he started buying when Bitcoin wasn't priced this high which had given his savings a boost, now when Bitcoin hits $100k per unit, his savings will have huge value regardless of how much money in total, in fiat, he had saved so far.