indeed the main role that is able to influence market prices is that of the whales who have a large amount of bitcoin, they can easily play market prices, although basically market prices can change according to the demand and supply of many people but the role of whales can also be a major factor capable of changing market chart
Some other whales having more than 100 BTC could easily make an altcoin pumped to the moment that it could look like hyped and bullish, but in terms of bitcoin, it needs not just a whale but many people who just wait for one another's move to make a change to the market. Basically, with their actions, people like us who doesn't hold allot of bitcoins are just following their signals to make some profits which is indeed, turns out for us to be manipulated without us directly knowing it. PS. Being manipulated doesn't necessarily mean negatively.