I have been using kucoin for years but never had any misfortune of getting scammed nor seen anybody having the same thing. I have had countless deposit, trade there as well as p2p deals, and like i said never a issue. So I'm not sure whether it is a scam.
CMIIW, but kucoin was launched in 2017 so it’s been 8 years and it’s still functioning so I think it’s pretty safe to say that it’s not a scam. I have heard it plenty of times but maybe for some it’s not as popular as say binance so there’s some hesitation about its legitimacy.
I have user othe cexs like binanace bybit the experience was the same as kucoin. Anyway, even if it is a reputable exchange it is always advised to not to use cex's to store funds. Because they can confiscate it at any times. Remember not your keys not your coins.
Not to mention it can also get hacked. There’s been so many cases where cexs get hacked and the money gets stolen even though you didn’t really do anything wrong and it was the exchange’s weak line of defense that got you in trouble.