Let's say a person is on vacation and doesn't worry about anything and doesn't read the news. And at this time, the exchange where he keeps Monero is delisting Monero. And time passes, the user visits the exchange - and what happens with his amounts on exchange that was be in Monero?
Why would you even keep your money in an exchange you do not control the private keys? Have you not heard about the popular phrase "not your keys, not your coins"? It is always safer to keep your money in a private wallet which you control the private keys to avoid cases like this.
For whatever reason you have your money in a centralized exchange before going for vacation, a lot of factors will determine your fate such as the reputation of the exchange, their policy and probably the laws of your country. For reputable exchange, they will leave the withdrawal for as long as necessary but will not accept deposits and trading and in some cases, they will convert all your assets to stablecoin after a given period of time. But scamming exchanges, your money will be lost.