You are missing something here, the the idea behind the DCA method was designed to meet the need of those investors who wants to owe bitcoin but don't have the money to finance their desired level of bitcoin holding at once.
I don't agree with you, the dca strategy is a strategy that anyone can adopt regardless of their investment sizes, even individual with substantial capital benefits from it.
Putting it directly to you that the major aim of the dca method is to offer a structured and disciplined approach to navigating the unpredictable market condition for investors accumulating Bitcoin for long term purposes other enormous advantage of the dca are secondary . Therefore an investor can buy a fixed amount of Bitcoin weekly or monthly without disrupting his other needs depending on his financial capability and a well structured plan towards his investment, including making the availability of emergency and reserve funds and taking care of his personal needs.