It's not uncommon to see people use apparently derogatory words among themselves to increase the togetherness of community, and so does Japanese internet society, as a long tradition.
You can find a number of such Japanese memes like "that's terrible", "absolutely crazy", "the author's sick" etc. which actually praising their eccentricity as a sign of creativity. I guess English speakers could easily get the nuance, too.
The here, too, just plainly means "crappy", "trash" or "nonsense", but also serves for multiple purposes: to show authors' modesty, to suggest their novelty, and to represent collective unity.