If a hack happens once, that's understandable.
Repeating the same hack in the same way across multiple blockchains is deliberate negligence. If these platforms don't care about their security, I don't understand why they continue to be used.
(This assumes we ignore the importance of decentralization.)
If same exploits always happened to multiple chains, this is actually points out that this is not accident anymore. Its huge failure to pay attention on the security of their chain or platform.
If they will not pay huge attention on their security and invest to tighten up their defense, the hackers will provably target their platform and find ways to exploit their system. The problems is despite of those exploit or hacking incident happen many people still trust their platform.
Once they notice that the platform or a chain is ignoring those basic security, best for people to be precautious, since same situation might repeatedly going to happen.
But well they are now back
https://blockport.io/latest-news/cronos-restores-chain-after-75m-tectonic-exploit and majority of those stolen funds still got frozen on Chronos.