I'd say he was just joking, if I had to guess. Maybe not, but I know I'm not opposed to joking around with fellow short guys about their and my height, making light of it.
Manlets rarely find someone shorter than them, so when they do they have to lash out cause nobody else takes their guff owing to their short height.
I've found the opposite of this to be my experience in life, this seems like shit reasoning to me. No one thinks along the lines of "oh finally someone my size, I've been dying to do some bullying for ages now"
Short men are the one's used to being teased and put down, they know what it's like, and as far as I can tell that makes them far less likely to do it, especially out of malice. Not to mention, it would only ever happen one on one, since if a short guy jokes about another short guys height around other men, the average/taller males will always take the opportunity to call him out on it and turn the insults back on him.
Taller men are the only one's I ever see actually lashing out on shorter men. And why wouldn't they? If you insult a short guy in public, any sense of respect is imminently ruined and everyone in the scene sees him as pathetic, and even if it's not in public, likely the shorter guy can't do anything but take it due to the physical inferiority. It's a consequence-free way to feel strong and masculine, and to climb the social hierarchy. That's just how it works, sadly.
I suspect there is also some confirmation bias in play, too.. you're so used to seeing normal males shit on manlets, that when another manlet does so, it sticks out in your mind, clearly.
