This is academic. You've all got the same facts to work with.
Who's right? You're all right once you subtract the empty spin and rubbery rhetoric, because you're all citing the same facts.
We haven't won a European trophy during Wenger's tenure, but there aren't a hell of a lot of clubs that have done better than us in Europe during Wenger's tenure, and PSV Eindhoven certainly isn't one of them.
Call it what you like, mid-tier, upper-mid-tier, no-trophy-tier, record-breaking-qualification-streak-tier ... the facts remain, the rest is just the usual tale of sound and fury, told by Biggus, signifying nothing.