The DCA method is a method that requires time to carry out, so it can only be carried out by people who have enough patience, especially when it comes to continuing to buy Bitcoin and not wanting to sell it again in the short term in any condition. This means that this method is usually used more often by people who like to collect and accumulate more Bitcoins before making a target release back into the market at a duration that ordinary people cannot predict.
You are right! The DCA method requires a lot of patience to operate, which is a method of depositing bitcoins over a long period of time. This method is only applicable to those who have enough floating cash because the DCA method should generally be run continuously so that the unit price will decrease over time through successive purchases and more and more bitcoins will be added to the stash. Regular accumulation can build up your portfolio to be fairly decent enough to reach that size within 2 years. At the next level you can be aggressive in accumulating which is to own more assured holdings within 4 years. You can drive for longer periods if you wish which is 10 years or more and guaranteed high future profits.
I don't think that the DCA strategy is not only applicable to be used by those who have enough cash float as you may say it, despite not having enough cash flow one can still use the DCA strategy with out having much cash flow since it is a process that help you accumulate more Bitcoin in different price level which you can be accumulating every week or month, I believe one can still accumulate more Bitcoin with little cash flow since you are not buying everyday but weekly or monthly as the case may be.