Investing full-time requires you to devote most of your time and energy to analyzing markets and trading. Moreover, the price fluctuation of Bitcoin is unstable, and there is no guarantee that it will always be profitable.
I don't think you have to spend a lot of time and energy on making market analysis if the asset you want to invest in is a very well-defined asset like Bitcoin. In addition, if an investor who prefers to invest long-term in Bitcoin, I don't think the investor needs to devote all his time and energy to watch the market every day, although it would also be better if an investor could have time to watch the market every day after investing. Because in general it is part of an investor's duties when he already owns the assets he is investing in.