There are no answers. It's a game. If you enjoy the freedom of tabletop gaming so much, instead of attempting to rationalize video game mechanics, why not just stick to tabletop gaming? CRPGs have never been a true emulation of the tabletop experience, and I don't see it ever being possible to really replicate it.
Because a CRPG gives me a chance to roleplay without the need for other players. I like single-player games, which tabletop games are not. That they are immutably multiplayer is what is wrong with them.
And I suppose CRPGs are, too, in a way, as I'm playing with the developers, but they're not here when I do it.
In regards to you disliking the game pausing when managing inventory, shouldn't you also object to being able to pause combat to issue orders?
No, because that's something that isn't happening in the game world. Me moving my mouse around shouldn't affect the in-game events. If the game doesn't pause then, it becomes a test of my mouse control, and that doesn't make any sense in the setting.
To some degree, that's also true of inventory, but digging through packs is actually something the characters do. Ultima VIII handled this really well - your backpack was a small UI element into which you dropped icons for your gear. And they sat there, overlapping. If your bag got too full, you had trouble finding things. If you kept it neat, finding things was easy.