Those people who get that tendency to be emotional caused by the smallest negative price movement of Bitcoin are those people who want to take profit in fiat. HODLers are in a different mental state. They WANT those DIPs, whether they're buying the DIP are doing DCA. It's simply another opportunity to buy more units in Bitcoin.
Plus if you're a HODLer you should actually have a good understanding of the basic technical side of Bitcoin. It helps not to panic because you know Bitcoin has massive potential value, although sometimes there might be some anxiety. We are still humans.
The truth is that, those that are emotionally occupied with price action have no place for long term holding, and they can't make up for a good DCA position since the lack the requisite knowledge and frame of mind to undoubtedly take action on the market and achieve a position, this is very important to first take care of before any other things, so anyone that is emotionally unstable should at least stay away from the market for a well good time, and after the build the needed knowledge about price movement and when best to take action then they can return back to buy in some lump sum and take the right position.
On the other hand most of those that have made some positive progress in the DCA position have always have one thing to say about the one thing that fundamentallly helped them to achieve such a financial state, which is persistent buying of Bitcoin at anytime there is an opportunity to buy more and take a position, most times arriving at a financial goal through Bitcoin may be hard for those that lack the consistency to take position frequently, and most of those set of people are those that may lack the right knowledge and commitment to make continues progress in the DCA journey.
Long term holding is the best way not to lose our on the future gains that the market present, so not taking action along market sentiment will ease you up alot, and in doing so you have to note that you only lose when you sell your Bitcoin at below the price you bought it, that is why you have to have long term perspective and goal before you start your Bitcoin accumulation journey.