This episode is bad but let's not blow it out of proportion. What you say is 100% true, but the true failure the episode highlights is that people who lost their fund had 1 single point of failure.
It would have been enough to add a moderate passphrase (the most underrated aspect of self custody imo) and no funds would have been lost.
This is all to say: gotta have at least 2 points of failure, and adding a passphrase was such an easy step that would have given at least 2 point of failure
My humble opinion
