How can someone hold that kind of money in a centralised exchange? Not to be harsh, but the person typically got what he deserved. Coinbase is one of the exchanges that can easily freeze users funds once they suspect anything or the 3-letter government agencies ask them to do it.
Even if you want to hold money in a self-custodial wallet, it shouldn't be centralised tokens/coins. The worst of it is tether; they can freeze your fund while it's in your private wallet immediately. The government asks them to do that because they are fully open to obeying and taking orders from them.
Maybe they thought it was laundered well enough and were waiting to cash it out.
If i would have millions in crypto, frankly i would see Coinbase as excellent centralized option. It would be way safer then anything i could provide, and i wouldn't need to lose any sleep over losing my private key.
But that's only because i don't have any reason to believe i would be targeted by government officials / police. If i was a criminal or blacklisted by sanctions, then obviously CEXes wouldn't be an option. There was a reason why CEXes got bad name, but that wasn't because governments were freezing assets, it was because of exit scams were that common. Now when they aren't, most cexes are way more legit way to store anything.
It's against cypherpunk ethos i know, but if we act like financial institutions and governments getting in crypto investing is normal, we might as well endorse them.