Actually, no he's not. If by "his own side" you mean Democrats, there are quite a large number of true liberals calling out Democrats, and Glen Greenwald tends to show up as a guest on many of their shows.
Check out Uprising with Krystal and Sagaar on The Hill. He's a con, she's a real progressive who calls out Dems all the time. Check out Useful Idiots on Rolling Stone -- two progressives who call out Dems in every show. Check out anything by Chris Hedges. Check out Jimmy Dore -- Greenwald is on there a lot. Check out Abby Martin, Aaron Mate. The list is much longer.
