On the other hand the design is partly the fault of DnD in general. The "heroes" of this universe are very quickly super beings who mainly do the big stuff, sadly. The setting you describe for BG1 sounds bucolic but how can a group of nobodies become semi-gods over the small timeframe a game takes place? Which they do. That's actually nonsense, more nonsense than to be accompanied by a vampiric elf and been confronted with mind flayers at start.
Sorry to pile in but I think you're being a bit hyperbolic here. No character or companion in BG1 becomes a demi-God. Characters in BG1 reach level 8-10 if I remember correctly?
The only character in the original BG games who evolves into something eventually approaching a Demi-God is our player character but that seems mostly on account of his rather interesting background (didn't want to post spoilers here). The game doesn't not seem to imply taking place over a short time frame either.
