You're right -- 3 good songs is probably a slight exaggeration (I would say 2 great songs, and 1 quite good one. The rest I can happily live without). Of course there are committed fans who think NLOTH is one of U2's best albums, just as there are people who think Self Portrait is one of Bob Dylan's best (for example, my dad thinks this). But the general consensus amongst music fans, including past/current U2 fans, is that NLOTH is an average-at-best U2 album, which added nothing to their legacy.
I happen to support that consensus. That doesn't make it "correct" -- no opinion expressing one's taste is -- but it does lend more support to the blog-writer's perspective than to, say, doctorwho's.
Fortunately, the fanboy super-snob fan always has the easy out of saying: "Most people are idiots! Therefore, if and when my opinion is in the minority, I'm right because most people are idiots." False logic, but if helps people sleep at night, it's all good.