So i say again if u want to keep some money for trading on an exchange fair enough, but if you are using that has your primary form of storage for your Bitcoin or other cryptos then you are only asking for trouble.
Yeah, that's kind of my point as to why this "proof of keys" movement is pointless. In the case of this KuCoin hack, then in all likelihood everyone who tried to withdraw their bitcoin on January 3rd would have been able to do so without any issue. If they all then deposit it back the next day, then it has made exactly zero difference to their safety, and they would all still be in the same boat they are in now with the exchange being hacked, funds being locked, withdrawals being frozen, etc.
Part of the reason people leave their coins on an exchange is because they are too lazy to spend a few hours to learn how to safely set up their own wallet. If they are willing to go through that process just for the proof of keys day, then they would be willing to go through that process any time for their own safety and security.
Better for everyone to just teach newbies to withdraw any coins they have bought as soon as possible, and to keep their coins off exchanges permanently unless they are being actively traded.