I don't think INT vs CHA is the main reason that wizard is bad - it is mostly that metamagic and sorcerers got buffed so much and wizards didn't and suffer from benefit as much from their flexibility as they would in PnP.
Admittedly, Sorcerers have been plaguing the series since the start. In the original games they were a 3E feature shoe-horned into a 2E D&D game. They did not even have a main stat. And as with BG 3 and their homebrew, the HLA homebrew of ToB also buffed Sorcerers since their main drawback ended up not being applicable to level 10 spells.
So at least in this regard it's a worthy successors
