Yeah you have a point but perhaps DCA strategy doesn't really mean accumulating every moment, you can also accumulate whenever you feel you have some funds to accumulate Bitcoin, you can still accumulate even when your salary is not enough perhaps let say you are earning a certain amount on a monthly basis it doesn't necessarily mean you should start accumulating immediately were as you no it will affect you at the moment, but perhaps if after the end of month you were able to save an amount that could last you more than a month perhaps you can use half of the current month salary to accumulate some Bitcoin were as you still have a good amount in your reserve account that could even sustain you more than a month, with this method even with your small monthly salary you can be accumulating ones in a while and before you no you have gotten a big portfolio, I had similar challenge like this when I started accumulating and this was the pattern I used to accumulate and it worked for me but now I have other business that's helping me to accumulate on a weekly basis now.
I think by having a reserve fund for a few months at least it won't be a concern because we can sustain on this fund.
Cutting half of the monthly salary I think it will be quite heavy, but we conclude to cut 30% for bitcoin it is more than enough of your salary, the rest can be used for a month's needs in the 70% allocation - because if you force to cut half the salary without any reserve funds in the account then it will be complicated when you have an urgent need.
Unless we have other sources of income, then the DCA strategy can be done every week if you only rely on a monthly salary then accumulate as much as you can, don't force it to be an obstacle later.