We don't have to wait till we have a strong financial foundation before buying Bitcoin, if we are very intentional about buying Bitcoin then buying by installment with as little as we can as you said can be good while working on our financial situation simultaneously, Bitcoin will always be available but it might be higher than what it is now, we should buy Bitcoin whenever we have that spare money to buy Bitcoin to make us become a Bitcoiner taken us off the no coiner zone and should only buy again when such money becomes available again.
There is no harm in starting small, investors who have little sizable amount that can accumulate fractions should make use of the opportunity. I would also advise small sized investors to conserve some capital in order to get more fractions at a lower price during the dips, that wouldn't stop them from the little they can DCA, the most important is doing the whole process of investment right without exceeding their financial ability.