The post to which you're replying didn't even mention Reddit.The post I replied to specifically mentioned Reddit. Although that was later edited out, it is hardly necessary given that the entire story is about a post and discussion on Reddit.
Being a jackass isn't somehow excusable just because you don't know who you're being a jackass to
While no one said it was excusable (at best I implied that it was ignorable), at times people want to take ownership of offense and leverage if not exaggerate it to prolong exposure, which is exactly what is happening in this case. Naturally played out, Internet memes have a half life of about a day, after which they would naturally be forgotten.
Secondly, while this seems counter-intuitive, the discussions on Reddit aren't about the subject (in this case guy on typewriter in NY city) -- they're about a contrived representation that is essentially a created fiction (the fiction in this case was "guys who try to be different by bringing a manual typewriter to parks -- hipsters!", which has absolutely nothing to do with "performance artist making a living". The guy being discussed on Reddit is not the actual guy in the picture, and few confuse the two). I called the discussion itself performance art because it really is -- people aren't trying to insult the guy literally, but instead are engaging in the banter of Reddit, which is something that exists unto itself.
There is another post in here by a guy whose wedding picture got appropriated for a meme, and while he took it in stride and seemed good natured about it, and while it sucks when the internet machine appropriates one's stuff, that meme has literally nothing whatsoever to do with him or his wife or anything at all to do with their life. In that case, again, it was simply representative for people to discuss, essentially, marriage. Just as typewriter man is simply a stand in for the purported hipsterism. People needn't over-personalize this stuff.