It seems that the price of Altcoin has stopped in one place and is getting lower. If the price of Altcoin stays at that fixed point, then it is very difficult for the price of Altcoin to fall. If the price of Altcoin now becomes too high, then people will start buying more and more, which will cause the price of Altcoin to go up. Is that right?
Yes you are right, all the currencies that are not stablecoin will easily decrease or increase their price base on demand. If many people are starting to buy for example Eth then the Eth price will increase it's price dramatically as the demand is there but once the holders will start to sell their Eth then the price will also decrease.
That is how the crypto market works, altcoin prices didn't stay at a fixed point even stablecoins as there are a little movement of their price like 0.001$ something like that but it will not affect that much compare to the currencies that are not stable as they can easily goes down like half of their price in just a day or even worst if the dump is there.