Of course, if it is possible to hold Bitcoin in the long term, then such investment strategies must be adopted. Investments are usually only profitable if they are long-term, but investing with a small amount of money can be done long-term only by following the DCA method.
Buddy you might be having some misconceptions about investment but investments are not "only" profitable in long term, short term investments too are profitable but you can't obviously look into that as an option in bitcoin because we consider with as wagering or gambling but which is more important to shitcoiners because they can't obviously hold those coins for long term.
Many people use many types of strategies but the DCA strategy is one of the most popular strategies, where all investors have found success using the DCA strategy.
Of course DCA has become the most powerful strategy in bitcoin investment because of it's benefit and how comfortable it is when it comes to time and resources management. but one must have to examine themselves to know what strategy would be best for them to adopt even though DCA would still my suggestion for any one but it's necessary to examine ones self before adopting any strategies.