Earlier quoted context omitted.
There is really no excuse for what he did and most other businesses would have fired him immediately. Reddit simply has a very immature corporate culture. Post-IPO (if they get that far) I would expect a massive clean-out.
What's the harm in such a pointless joke? It was silly, but it's not like the meme subreddit he did it to was a super serious one like AskHistorians is.
The clear harm is that Reddit posts have been used in court cases. People have and will go to jail based on that content.
The unclear harm is they use “we’re being professional business” as an excuse to do unpopular and unfriendly things and also “it’s just a prank bro” when stealth editing posts... no dude. Can’t have it both ways. No one should trust this company at all, and they’re proving why.