Inasmuch as most investors that are financially capable may likely be nterested in buying Bitcoin at once than buying by parts I still believe there is still need to know the best strategies that will be more favourable because if one is equip with the right information it gives more confident and determination to make more significant investment.
DCA strategies is more leverage to accumulate Bitcoin and I think most investor will consider it more preferable.
You just have to do your research and know the strategies of investing bitcoin, you can know the best strategies that will suit you according to your income and how you can invest bitcoin with ease. But in all the DCA strategy of investing is still the best of buying bitcoin for all. DCA strategy is a method of buying that helps investors in making good plans of how to buy just according to what can be afford, with this investors won't find it difficult on how to buy bitcoin because their is already a plan on how much that will be spent in buying Bitcoin.
This is also a strategy that helps investors to be consistent in buying Bitcoin to accumulate good amount of Bitcoin, which I will also say that DCA method of investing encourages discipline in accumulating bitcoin and also encourages the mindset of longterm investment in bitcoin.
Discipline is built through the knowledge that you've got. If you know the facts, you know why you should wait / hold / act up in the needed moment.
Simple truths, and indeed, - any person is free to choose his own way to invest in BTC.