@Merilirem I mean you can say he's conveniently dense, and you're right, but he's all around dense too. Despite having a dream of magic, he's AMAZINGLY easy to sidetrack for anything. This chapter demonstrated that pretty well, despite finally getting his first wand, he was taken off course multiple times.
He has a dream, but he does not pursue it staunchly. It's kinda a childlike dream, if anything. "I want to get there, but I'm not going to actively pursue it too much".
In general I'd agree with MC being conveniently dense being a big annoyance, but personally, since his denseness is consistent in all fields, I think it's proper. It's not him acting in an unusual way for plot halting, it's him acting his normal way for plot halting.