It depends on what you mean by retiring on bitcoin!
Are you retiring as bitcoin trader or as a miner or just as a long time investor.
Because why I had to ask this question is because, if you're long time investor on bitcoin, and over the years you've gotten a good return in investment, that could save as a retirement package for you, but you should understand that it takes of lot patients and expertise to continue to Maximize profit and sustain profit margins over the years, because this is a life time journey.