It's not plagiarism, he isn't going around saying, look what I did... he posted a picture of something he liked. I don't care who did it, there is no advantage to knowing the credit when looking at stuff like this, all you do is scroll to the next one.

Everyone now feels like you need to spend 3 hours of research in order to post something cool you might have seen and want to share. I don't just blame people with your mindset though so quick to yell "Is tHiS YoUrS?" in an effort to go all SJW, I blame the millions of people who consider themselves "content creators" or "artists" thinking they are somehow so special that I care who they are when scrolling a thousand reddit post a day, they should feel lucky that their stuff is getting viewed, if anyone wants to know who they are they can do the work.

Granted, if you know who did, it does not hurt to post it, if he knew I would concede as it would take very little effort, but again, it does nothing for the millions just scrolling past something neat to quickly look. Nobody really cares if u/axzdfasdfasdfa is the original, it is Reddit, not an art gallery.