Considering it's market cap and the numbers of investors involved, whales manipulation might be a difficult thing to say when it comes to Bitcoin. But we can't overlook the effect of news and rumors. Bitcoin just went below $54K some minutes ago, with no clear information on what happened or who is selling. This is a clear opportunity for few individuals(not sure of who they are) to start passing rumors inorder to push others into selling, so they can buy the dip for themselves.
Whales manipulate the market more when there's fear in the market and the price of Bitcoin is declining, as the market has seen a dip most whales will use this chance to push for fud that'll see the market fall further so they can buy when everybody is panicking to sell. All cryptocurrency gets manipulated by whales but there's less manipulation because of the marketcap of Bitcoin. Whales know that there are many investors waiting for the dip to buy hence their manipulation will be favouring others and not only their own self which isn't what they want because whales are greedy and what to make the most profits from the market through manipulation. To see the whales in full action is to observe some altcoins like newly created altcoins and you can see them manipulating the price. When whales are manipulating the price, don't fall into their trap and be panicking like most people in the market do that don't have experience will be panicking but be buying more.