I did love Garfield during childhood, and my experience was very similar to the poster's - I just sort of grew out of it, and eventually came to the same conclusion that the article did - Garfield wasn't ever going to challenge anyone mentally 'cuz that's just not what he was designed for.

However, I do remember reading that series of strips in one of my grandfather's Garfield collections, and being seriously creeped out by it. So I could see the rest of the strips being Garfield deluding himself whilst slowly starving to death - it would certainly explain their banality, if nothing else. =D

(Also, existentialism!Garfield rocks. I laughed for hours when I first saw that page...)