Let's ask, though, would you prefer a broken game you can mod to your wildest desires of a functional and good game you can't mod all that much? And before you say it, YES, at this point in technological progress, those two are mutually exclusive. Even the Source engine proves that to be easily modifiable you have to sacrifice large-scale worlds.
As you've described, in an engine as easily modifiable as the one Bethesda uses, bugs are bound to come up. However, the issue with them I find most irritating (and, based on the OP, I assume most posters here do as well) is the sheer lack of effort Bethesda undergoes to fix these bugs.
I won't pretend to know why that is, be it sheer laziness or issues with release date; I assume it is the latter, as I recall them having to delay the game and it being surprisingly functional on release (by Bethesda standards, anyway).
But let's take a few of these fixes here:
- Fixed an issue where subtitles would occasionally not update properly
I first experienced this bug with the Vault-Tec representative. That's literally the first dialogue you have in the game; not only it should've been fixed before launch, but at the very least it should have been fixed with the first patch, not the second one.
I'm not going to go through the rest of the bugs OP listed, mostly because I basically agree with everything they've said and I'd rather not waste anybody's time repeating myself.
Rather, let's take a look at the bugs fixed by the mod 'Simple Bug Fixes' on the Nexus by MookittyBonnie.
http://www.nexusmods.com/fallout4/mods/2142/?
-Big Leagues 5 gives its damage bonus correctly.
As pointed out by the mod author themselves, this bug was explained as a display bug; however, this was a lie, showing a distinct lack of play testing and professionalism.
-Targeting HUD now turns off in dialogue, allows you to use pacify effects, and no longer causes neutral NPCs to go hostile.
This is also another very infamous bug; the Targeting HUD is a power armour helmet mod that allows you to highlight living targets but, for some odd reason, would cause friendly NPCs to turn hostile if highlighted. This isn't a hard-to-find hidden bug, this is a quite obvious oversight in the game's programming, and should have immediately been found when testing the mod (the power armour mod, not the bug fix mod).
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Killshot reduced from 2000% to 20% accuracy bonus.
Another infamous one, and pretty self-explanatory I like to think.
The list goes on, but my point is that Bethesda clearly didn't play-test this game to acceptable levels. Most of these bugs are easy fixes (as shown by the fact that somebody with none of the tools the developers are using managed to do it) and shouldn't take more than a few minutes each to fix for someone using the developer's tools.
Bethesda's faults isn't in the existence of bugs in their games; that's a well-known engine limitation, and the price they pay in exchange for an easily moddable game. Their fault lies in their blatant neglect to actually put any effort into fixing these bugs in a fast and efficient manner.