I think you misunderstood something about the DCA method and the fact that DCA method is a gradual process of accumulating Bitcoin doesn't mean that it's mainly for investor with little Capital even rich investors do
Some people feels DCA is met for those who are not rich but that's not true, just like lump sum strategy are best for those who got an inheritance from there father, mother, or anyone at all or someone who had the opportunity of having a huge amount of money, DCA are met for those who receives there money week, monthly or yearly is for those who chose to accumulate with time.
So the DCA strategy is for those who receives small salary and those who receives big salary, one can decide to invest $5k weekly or $100 monthly it all depends on your Discretionary income.
There are several strategy for those who wants to invest in Bitcoin and one can only choose the one that is okay for him or her.
Actually an investor can choose more than one strategies when investing in bitcoin. Provided you know how and when to apply each strategy. So don't just think because you used one strategy to make your first buy, that you cannot utilize another strategy when you want to make another buy. You can also decide to divide your money into 3 parts, depending on how much you have as your investment capital. One part can be for lump summing, DCA, and another fraction for buying when bearish. This way you have seen that the investor has been able to make use of all the investment methods with the same amount of money. And he stands a chance of benefitting from all market conditions.
An investor can still decide to focus on using one strategy to invest in Bitcoin and succeed so it is not necessary that you must apply all the strategies while investing but the best is always investing with the DCA because you won't miss out at buying during DIPs which is the most important part of any investor who is still in the accumulating stage of their investment, lump summing is good for some people but I don't consider it to be a good strategy since you can go an all in and never invest again therefore you may never increase your portfolio and for buying at DIPs, it's also a very complicated strategy because you can be expecting a DIP and it may not come and you end up not buying so basically using the DCA is just the best strategy because you can also decide to increase your DCA amount depending on your cash flows before your next DCA as it can help to increase your portfolio with time.