I don't just hear, it's something I see all the time in the crypto market, right now if you go to Dex screener and check all the meme coins, they are been manipulated everyday so it can favour their own plans. Only traders with huge money and influence can manipulate the market, though only influence work on Bitcoin, you can't manipulate the price for Bitcoin with money because it is too huge that's why only influential people can do and undo.
However, altcoins are the main manipulated coins, someone who has a large number of YouTube and directed his subscribers to buy a particular coins and the demand can skyrocket the price and sometimes they even team with people that has money to move the price of a coin, they be doing the shilling while the money/market makers be doing their thing in the background and this is made possible because it's very easy to manipulate the price with low market cap and small number of holders.
Lower cap coins and tokens being manipulated is one thing that we can all agree on, there is no doubt about the fact that there is manipulation when the volume is low because you do not need a lot of money to manipulate something like that. Whatever can be manipulated with just a few million dollars could be and will be manipulated, even if manipulation hasn't happened yet, it will happen eventually.
What we need right now is something much bigger, something so high on volume that a few million dollars wouldn't change a thing. When it comes to bitcoin, I do not think that there is a manipulation, not big anyway, we decide what is going to happen and if we want to keep bitcoin high then we will just buy and hold it high.