This is not peculiar to shitcoins, because, by the definition of shitcoins, I believe they are referred to as worthless coins, unlike the way people make many good coins look like shitcoins. However, what you explained is happening on all coin listings on exchanges, it is artificial, so it could happen on the listing of good coins as well where the coin on the exchanges' chart would indicate some dangerous peaks and bottoms.

Well, I am happy to tell you that you should disregard those peaks and bottoms, they are not real. I've witnessed Binance and top exchanges listing coins and tokens with dangerous bullish and bearish performances that are nonexistent. All you should take seriously in this regard is the present price of the coin/token and the current behaviours which I advice you to study for a long period before making a decision on the coin/token.

More importantly, it is good to research the projects effectively to know whether to buy them or not, and not rely on the nonsense chart representation on exchange platforms that has been inflated and deflated with no good explanation for it.