No one knows the answer. Take the risks. You are the one who will make your crypto journey be successful.

My own view:

Crypto earnings can really give us a good and decent in the long run. Like every other investments, you should know and understand the risks you are dealing with. Meaning don't just stick on one method if the goal is to secured your funds after retirement. If such cases, that only crypto investments is your preferred method then improved your method and take advantage of every trend.

List all your doubts and analyze what would be the best solution. For example, you aren't sure if bitcoin will last forever, then take the ride today before it will gone. Relying too much in the future of bitcoin may just wreck your expectations so stay on reality.