Solid isn't too difficult to achieve with what it's trying to do, considering the developer and the experience they have with this sort of game. I just didn't think it was solid enough to be considered a good game to me personally. But of course, that is a subjective matter, so I understand.
I look at it like this, I criticized that game endlessly while I was playing it, I thought about all it's issues afterwards, the shitty things that existed in that engine since Morrowind that were never fixed and so on, it improves over Oblivion in number of ways while also unfortunately taking steps back in others.
It has a lot of issues here and there, but then I realized over time as I'd go back and play it again or play a different character, I realized I was sinking a significant number of hours into it, if I really didn't like Skyrim, I wouldn't have sunk 80 hours into it in the first place, let alone like 100 more, so it grew on me, I ended up appreciating it for what it is and stopped being so bothered by some of the issues, which caused it to become much more entertaining.
Basically, aside from the Witcher 2, which probably beats it in a number of areas, I have the Dark Souls 2 outlook on Skyrim, it's not nearly as good as it should have been and should deserve to be criticized as such, but it was still more enjoyable than a lot of other games around that time, to me anyway.
Both of the major expansions are pretty damn interesting to play.
But you are right that Bethesda should be better than they actually are.