Developers have been using the old "there are too many PC permutations to test" line for years. Fair enough, there is some truth to that and it is likely that certain hardware and software combos in the wild will turn up bugs that couldn't have been easily tested for. However, when you get a plethora of crash/freezing issues on consoles with fixed hardware and software, that excuse wears a little thin. And when some of those issues have existed in two previous games, well then surely some questions should start to be raised? If not then, when exactly would you speak up?
You may well have had a fairly smooth experience. That's great for you - many others didn't. I personally managed to finish the game on PC, but not without numerous crashes, performance issues, and miscellaneous gameplay bugs left right and centre. The fact that every single review at the very least mentions bugs should communicate to you that this is not an minor issue. And it's not just something limited to Bethesda or Obsidian (although they are obviously masters at it), it's something that pervades the entire industry. I find it mind boggling that game developers/publishers seem to be able to walk water on this stuff when I, as a business owner, would be crucified if I put out my products with as many technical issues. The fact that they are peddling entertainment software as opposed to some "physical" product (like a car, etc.) doesn't mean they should be held to some lesser standard.