Yeah, DCA can be very convenient for both rich and poor but I think it's not really the most convenient way to increase ones Bitcoin but rather it depends on the investor's capacity or level of income. Those investors who uses the long sum strategy may/can not consider this strategy because DCA is a gradual way of acculturating Bitcoin therefore a lot of consistency and discipline is required or needed in other to achieve the goal.
At times DCA feels like someone just trying to have some Bitcoin, to them it feels better to have some Bitcoin rather than none, but for me it is different, because every Bitcoin counts.
Either rich or poor you still need to apply some common sense when using DCA strategy, if you don't know about charts, like stochastic RSI, weekly candles and closes, etc you aren't getting the best benefit of DCA strategy.
If you keep using DCA strategy when there is some corrections in the movement of Bitcoin you will end up with more satoshi, and if you are rich and you can afford 1BTC on your every DCA days you can make an extra 1BTC easily if your entry is always on correction level.
My point is it is still dumb to buy Bitcoin when it is skyrocketing, you are simply cutting some SATs off all in the name of you want Bitcoin now.