I don't mean to be a wet blanket here! But between job loss, medical bills, car trouble etc, enough things can go wrong without adding financial ruin into the mix. Its sage advice not to put all your eggs in one basket. Even if that basket has the potential for big rewards.
You seem to be making shit up (which could also be referred to as a strawman's fallacy) in order to try to appear as if you are the savior, and part of the point of the thread is already getting into the consideration that prior to investing it is better to have a source of income.
Consider keeping some cash on hand for a rainy day, or diversify into other assets. Going all in on one thing whether it's crypto or whatever, leaves you in a risky spot if that market craters.
Fuck crypto and fuck diversification. Those are both distracting topics when we are talking about bitcoin here.
Anyone who is involved in the basic of considering whether to invest into anything and how much to invest does not need to get distracted into investing into a multitude of investments, and so there is nothing wrong with considering starting out with investing into bitcoin and also within that category figuring out how much disposable/discretionary cash is available to be able to invest, which gets back to the idea of having enough income to cover expenses .. and as many guys already mentioned, that whenever anyone starts to put any of his extra cash into anything besides cash, then the value changes relative to cash, so it becomes more important to make sure that he has an emergency fund that would take away from the need to ever have to dip into his investment, except at a time that is of his complete choosing.
Guys also mentioned how extra cashflow sources could serve as a kind of emergency fund, which likely is not as good as having an actual emergency fund, even though it can be a solution to increase your income and to lessen the risk that any one drying up of cashflow would result in excessive shortages in cash.
And, sure like you said there are all kinds of reasons that an emergency fund might be needed, which further justifies to make sure to build that part of anyone's preparations, even sometimes an emergency fund and investing into bitcoin could be done at the same time, but there may be needs to be a lot less aggressive in the bitcoin investment until the emergency fund reaches a size that is sufficient to cover emergencies that may come about.
I personally believe that emergency funds should hardly ever end up being touched because anyone who is already accustomed to earning a living and having expenses, realizes that there is likely needs for a float in the cash balance and also reserves for the times in which cashflow versus expenses may well fluctuate. Those are not emergencies. Those are anticipated variances within the cashlfow and the amount of discretionary/disposable income that might be available from month to month (or whatever happens to be the pay periods or the times in which expenses come due).