The thing is, his reasoning isn't even wrong (assuming what he said about the spread of PoCs and the ease of finding the vuln was true), but it clearly prioritized Chainguard customers over the broader ecosystem.
I prefer them going public over breaking the embargo as silently breaking embargos and publishing details about vulnerabilities to an uncontrollably large group of unvetted people is worse.
Chainguard will lie and cheat to put themselves first. Not their customers, but themselves. These are just plain facts.
You can't agree to an embargo and then just ignore it when you feel like it. What other things are you willing to go back on your word for, especially when you know for a fact you are putting people in danger.
I hope the broader ecosystem responds by putting their customers over Chainguard. The Chainguard customers can then get security updates after the embargo was lifted and Chainguard noticed.