Yes, we know investing in DCA method is much less loss and less risk. However, if your friend makes such a comment, there are some similarities between trading and gambling. Because if gambling is played a few times then there is a possibility of becoming an addiction, and later on you will be interested in gambling, just like if you start in trading then you will be attracted to trading later, in that case you will lose money there. As we know, investing in Bitcoin is the most profitable compared to trading. If you start trading then start in bitcoin it will not let you face loss, but you will get profit from here especially use DCA it will help to reduce risk all the time. We know it's always better to use DCA as a smart investment.
I think those who compare DCA investing to trading and gambling may not have even the slightest understanding of this investment yet. I would instruct them to read this entire
Buy the DIP, and HODL thread thoroughly so that they can gain thorough knowledge about DCA investing (as it has been mentioned here hundreds of times that a newbie can start investing with little knowledge of Bitcoin and little money). But they are right on one point that trading can be compared to gambling as there is maximum risk and profit uncertainty in trading just like in gambling. Through DCA method to avoid risk and reduce stress, we commit to holding bitcoins for a long period of time by buying and accumulating bitcoins over a period of time using a fixed income source.
What provably they know is bitcoin is all about buying and selling. They didn't bother to know other possibilities that could able to give them huge chance to gain from bitcoin if they just use the best strategy and choices towards on how they deal with their bitcoin.
If they think about trading and gambling would give profits easily sooner or later they would realize that its hard to gain consistently especially that market changes so fast and there's no assurance on every bets they made on certain games or situation around. Most likely they would face a lot of losses especially if they do bad decisions towards their trading and gambling activities.
To bad for others that they realize late that holding is more better so hopefully some other people who want to start up will just find good advices then select long term investment with bitcoin rather than wasting their money and energy on gambling and trading.