I'd say he's pretentious because the music he makes himself is the best, and nothing else comes close.
Maybe he has become more "normal" now, or had a change in personality, but when I read old interviews, he just comes off as a very cocky and arrogant musician.
I specifically recall an interview where he talks about One Hour... being his least favorite PoS-album, but proceeds to say "but it's still more original then most of the music out there".
Maybe he's right, but coming from the artist himself, that just sounds rather arrogant.
It's not the only example of him praising his own music and bashing a lot of other things either, he said something about Progressive-music, and he said that he stopped listening to Progressive Metal/Rock back when Awake was released, because everything since has sounded the same.
Guess what, PoS is also a part of that scene, so then he probably thinks that they haven't changed either?

And yeah, you might have a point that we PoS-fans do hold their music very high, but that still doesn't change the fact that he's rather arrogant about it.

A lot of artists has confidence, we have the classic "our new album is awesome"-scenario, but to bash so much else in music, and praise your own music so much, especially seeing as PoS barely goes around economically, would have been another scenario if they were the biggest band in the world and had tons of cash, but despite being so much better then everything, they're still smaller then a band like Opeth (who they are opening for this tour), despite Daniel Gildenlöw pretty much looking down on them.

Also, this isn't meant as a bash-post, I still really like Daniel, but he's quite... special.