Although this has not happen to our exchange where we put our funds for a long time, this should prove that its not safe to be there for months or years, you have to secure your money, or tokens/coins to your hardware wallet, or electrum wallet etc since you have full control unlike CEX.
Earlier there is a news that Coinex have been hack, where the hacker transfer and drain the wallet, with ETH, Polygon, Tron etc, i think this is the first time this exchange has been hack, i say i have coins there but no value, but if you have lots of eth and others thats is a major concern, since we don't know if they can refund the loses.
so to be safe store your bitcoin and other coins to safe wallet, like hardware wallet etc.
this is the link of the news :https://cointelegraph.com/news/coinex-crypto-exchange-suspected-hacked-crypto-moved
The major cause why people actually fall victims to such cases it's because CEX are way more popular than DEX and there is also the human nature of arrogance to blame because if you are truly interested in Bitcoin you would have known that the major purpose of having Bitcoin or it's creation was to avoid third party control involvement in your financial life then why would you choose to actually save your money in a centralized exchange which operate like the government.