eh, if he posted it to his page, meaning "don't make a post to MY fb page complaining about trivial matters. so many other people are so much worse off, and i will block you", don't really care. his page, he can do what he wants.
but if he meant, "if i read anything on any fb page about you complaining about trivial matters when so many others are having real problems, including on YOUR own fb page, i'll block you", yeah, then i'm going to save him the trouble of blocking me, because i'm going to block him. no one gets to tell me what i can and cannot post on my own page.
methinks that if it was scenario #2, he'll have a really complaint-free life, because he'll have a lot fewer fb friends to deal with.