I certainly do think that Schoenberg was a great song writer. The songs are mostly very approachable, too. I also love Herzgewachse. I am not a huge fan of Pierrot but do value Guerrelieder greatly. Both were seminal works.
I think you underestimate the "hipsterness" and pretentiousness of artists. Many people, even great ones, are susceptible to hype and group think.Dimitris had the ultimate respect for Arnold. He knew much better than me...