When you make a death threat, it's real.
How is Steam supposed to say "Yeah, those crazy kids said they were going to murder our CEO but we're pretty sure they're kidding"?
How could they ever have a business meeting or give them a tour of the facility or do anything together at all?
What that developer did was throw off the social contract and invoke the law of the jungle - and once you do that with someone, it's almost impossible to come back. Oh... now you're "sorry"?
How do I know this isn't just a ploy for me to let my guard down? There is no way to know because you've said that you don't abide by the social contract - your words cannot be trusted.
Everyone should stop and realize that if a person threatens to murder you - to your face - and if that threat is even slightly credible, you're usually justified in responding with force, up to lethal force. There are a lot of "it depends" in that statement, but if someone is seething with anger and you're actually afraid for your life, then you're justified in neutralizing that threat.
I worry that too many kids grow up in a bubble with no thought to just how serious they may be taken when they decide to lash out.