Fluctuations in the market price was never their problem, this is only accountable for newbie investors. If volatility of bitcoin was the problem of those early birds I don't think any would have successfully held their coins until today. When you have understand how the market operates and the major trend of the market it's easy for you to understand that bitcoin from a higher time frame is headed upwards irrespective of those minor bearish trends that tends to weigh newbies to panic and sell. When using the DCA strategy to accumulate there is no need to develop doubts to weather or not to invest during the peak price as long as your goal is to invest for a Long term, though this might be a problem for newbies but as time goes by they'll adapt to the system and understand that those are just little insignificant moves in bitcoin's major trend.
Beginner Investors need to learn a lot about how to invest so that they don't make mistakes in taking steps if they buy BTC in DCA mode it will benefit them in the future, after all, people who invest use cold money to do it, so even though they buy at a high price, it doesn't matter if they don't always look at the fluctuating coin price and don't panic if there is a decline and remain disciplined in investing.