Even those who are seen to have accumulated enough btc are still doing dca, meaning even though they had hold hundreds of bitcoin they don't care and they just wish to continue holding continuously, of course this is a good approach and is increasing their holdings, I don't really think those who knows the real value of bitcoin are yet to be satisfied on their holding, and even those whom term and seen to be whales always manipulate the market to stir up little traders or investors to dump their bitcoin so that they could accumulate very cheap.
DCA works perfectly right for those who wants to utilized the DCA strategies.