You are right that Exchanges should allow their users to withdraw their assets but in the bankrupt scenario, they don't have enough funds to allow users to withdraw furthermore they don't want that user to withdraw their coins so they suspend withdrawal and do like this.

Although, as of now, the future of the FTT cryptocurrency is something that would take a very long time to rise again. For now, the future of FTT cryptocurrency is dead, and investors have pulled out of FTT cryptocurrency.

I fully agree with this statement that FTT is dead now and no one wants to take the risk even Binance support it same was the case with LUNA, no one take much interest in its new form.

Good luck in this contest if you find time please read my Article too.