(1) Writer X states that “apparently such-and-such topic isn’t considered worthy of notice on this blog.” Well, most obviously, since X just raised the topic, it evidently is worthy of notice on this blog. But what this rhetorical trick is really intended to do is to communicate the idea that the Writer X is a discerning individual keenly concerned about such-and-such topic, unlike all those other people, who must be ignorant and uncaring.
(2) Writer Y remarks on topics A and B, expressing concern or outrage, say. Writer X then attacks writer Y, saying, “Ah hah, but you didn’t mention topic C, so it must mean that you are unconcerned about C.” Guess what? Writer Y also didn’t mention topics D,E,F,…Z, or the other eleventy billion issues that one might in principle write about. It’s impossible for Writer Y to mention everything going on in the world; that doesn’t mean Writer Y is ignorant or uncaring about D,E,F, etc., but rather that Writer Y has finite time and made some choices. It’s not about you, Writer X, so stop the faux outrage.