The passive income with bitcoin is very good and it is very simple. in fact bitcoin make it very easy that any body can generate a passive income with bitcoin. you to just buy some bitcoin and make a sense of the market that when the value is falling and when the value is rising and you have to make the best prediction also. buy bitcoin when the value is down and use them when the value is high but you have to make sense a best one.
What you are talking about fits in the category of trading, and for that reason can't be seen as passive income. Trading in every shape or form requires action from your side, while passive income means that you earn money or coins while doing absolutely nothing. Staking your POS coins can be seen as passive income. Lending can be seen as passive income. Mining to a certain extent can be seen as passive income. Bitcoin itself doesn't allow you to generate passive income by default. Even if you buy at a certain level, and the price increases with 100%, you still haven't gained anything -- gains occur when you sell or spend your coins.