Again, OP:
Without looking it up, can you tell me right now what happened in 2.3?
3.3?
4.3?
MAYbe you can tell me what happened in 5.3 (because it was unusually significant), but what about 5.2 and 5.4?
Yes, "filler" happens from time to time. Not everything is or was filler, and some exposition isn't bad for the slow kids in class or new players that haven't been absorbing all this lore and information for nearly a decade. Not to mention there has been new lore revealed, though you probably missed it by having your angry-goggles on as you did the MSQ. Namely, some hints at who Golbez might be and what he may have done to get there. And we also got to see the 13th - the actual world, not little sections of it - for the first time. Which is a pretty big lore reveal.
Opinions are opinions, but seriously, not every patch is a 5.3. I'd be interested in hearing you answer - without looking them up - what happened in those other patches and how they were all better than this one.
No, it's not just you. I think most reasonable people agree and see it as such.
I don't disagree with you overall except for this. As we learned in the Caster ShB Role Quests, Void Gates can, in fact, be made between the First and the Thirteenth, and travel between the Source and First or First and Source is possible, just...risky. Though it's also worked all three of the times we did it and the one time it was done to us (and arguably somewhat worked the five times it was done to our allies as it was TRYING to be done to us). Beq Lugg is a loveable worrywart. Yes, it could be dangerous, but people are sometimes willing to do dangerous things, and we know direct travel from the 13th to the 1st is entirely possible and featured pretty heavily in the Caster ShB Role Quest series.
What you seem to be missing is that's the problem. Imagine just watching the Tatooine scenes of Star Wars: A New Hope/Episode 4 and then complaining that it's a boring trilogy just about an annoying kid on a desert planet. You don't judge a story arc by looking at only a section of it. I mean, you CAN, but generally speaking it's a bad idea. You have to judge it as a whole and as it fits in the greater series/universe in which it's set.