Very juvenile and unprofessional way of dealing with the situation, really erodes trust in the platform (simply deleting the comment would have been a better response).
Would maybe expect this from the founder of a young fledgling startup, but the 33 year old CEO of a company like Reddit ought to know better.
If I read this Reddit thread without knowing him, I would have deemed him unprofessional and maybe even upvoted some of the comments.
When I read the thread knowing who he is, I'm thinking "I can't imagine how stressful it must be to run Reddit. He made one mistake in a bad day, apologized for it, and now everyone's talking about it. Steve's way nicer and more professional than I am, so I would probably have messed up big time in his shoes."