All cryptos are volatile except stable coins but even with that, I can see some stable coins that have been moving under some cents and trying to depeg. And what you've said is a warning to those that like most memecoins. If they're in profit, that's nice but if they start to see themselves getting losses, let it be as a lesson for them to remember.
people seem to forget the fact that when someone cashes out big profit from meme coin there's people losing buying at peak, its not really profitable for many people but they don't tell anyone about their losses, at least with some coin with real product you got product that can be utilized but many meme coin trend are short lived.
in this case like as you mentioned even meme coin fall under category of altcoin and meme coins and other altcoin generally are just as volatile depends on the coin we are talking about here.
if its stablecoin indeed there's some case where the stablecoin are being volatile, i still remember when usdt and usdc has some value decrease, usually most of the stablecoin that depegs are made algorithmic stablecoin where they didn't really peg their coin to usd but to other coin to keep value.
Every market that you win, there's always the opposite side that losses. If that loser don't want to lose, they shouldn't get into this market. Because if they do so, they are aware that they can be a winner or a loser. Even if we want to get into the altcoins that have utilities and have real use case, the trend right now has changed and people have chose to get into memecoins. But despite that, there are still a lot of us that chooses to be into those projects that has real use case. As for the stable coins, they don't lose quickly their value but the known ones are unlikely to. But if they do, they decrease in value so slowly.