The original Baldur's Gate suffered from the same issue and while the impact of this can certainly be observed in certain aspects of the game, that didn't really stop it from becoming a classic. However, I don't think that can be all of it. Part of it is probably that PoE and DA:O are both games which use an engine that is new to the developers and is being adapted (or in the case of DA:O, developed) concurrently with the game.

I tried to think about the cause of this. but by practically all accounts, this is not the case. Given that nowadays games are being made by multi-decade industry veterans (Muzyka credits Feargus Urquhart, Chris Parker and Doug Avery for teaching Bioware a bug tracking method even back then) who by now must have streamlined and optimized all of these things to perfection, one would expect PoE (or, for that matter, even Dragon Age: Origins) to be much better than BG2. It's kind of interesting to see what the main concerns were back then: it's mostly technical issues like leaving all of the Quality Assurance until the end and a lack of communication within the team. It describes the philosophy and mechanics of the development process of BG2 and is sort of an executive summary version of what will hopefully be in the PoE Making-Of-Documentary once the latter finally comes out. I ran across an article today: Baldur's Gate II: The Anatomy of a Sequel written by Ray Muzyka (one of the co-founders of Bioware) all the way back in 2001.

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