Maybe DCA is more popular than other strategies because many investors prefer to use DCA compared to other strategies.
Because it works better and brings profit for most of investors who use DCA strategy. With DCA, it's more easily to succeed and get profit, because it requires simple steps and principles to follow. You don't have to play with technical indicators for any analysis. What you need is researching about fundamentals of Bitcoin, and the rest is going with DCA strategy.
To learn fundamentals of Bitcoin, here
The bullish case for Bitcoin.