The additional transaction fees that using ERC-777 would cost in the Ethereum network are probably much higher than someone losing half a million every now and then. So economically, adopting ERC-777 would be a step backwards.
I agree that deploying the full 777 would be too costly, yes, and probably open up reentrancy attacks.
But one simple check in the transfer function would have saved this person half a million. I would gladly pay that tiny extra bit of gas for their sake.
Economically, KYC in the real world is a step backwards. Economically, laws made to restrict trading is a step backwards. There's still a damn good reason we do it, but the crypto grifters seem to only see the economical part of it for some reason.
In that sense, crypto to me is like a consultancy taking a complex, legacy codebase and saying it'll be easier to rewrite it from scratch.
We see how that plays out all the time. Something shiny and new is produced but it completely fails to take into account why the original system was so complex. Given enough time, it becomes just as complex as the old system, if not more complex.
Satoshi is a pure ancap, the lack of regulations is a feature for them. Being able to be a grifter and scam people is a feature, not a bug to most of the cryptocurrency community.