Sometimes, simplification is not an inherently bad thing. Also different games work in different ways and aping what works for apples to apply that to oranges is not going to work well
Pillars of Eternity has a 6-character limit on the party. D:OS has a 4 character limit. That means that it's harder to fill all the roles in D:OS, and it would be much harder to be able to hit 4 different saving throws.
D:OS also has Memory to worry about, limiting pretty harshly early on what skills you have available to use. I can't afford to spend a slot on a skill which only removes one status effect, for instance.
The more different stats you have, the more numbers you have to try to keep balanced, which means the more numbers that will appear on loot. The more numbers which appear on loot and the more numbers you have to keep balanced, the more difficult it is to choose between different pieces of equipment which have numbers in different areas.
That leads to players eyes glazing over and them mentally checking out of the decision making process. This happens to me all the time when I try to compare equipment in games like Torchlight or Dragon Fin Soup. They have too many numbers and there are too many stats and so I basically stop caring about most of the numbers and just going for what roughly has the highest basic numbers.
True that, it worked well with Dragon Age Inquisition where it basically moved away from stats and instead focus on talent/skill trees. However it depends on the genre, DAI was aiming for action cum brawler oriented RPG(not to be confused with stats & loot driven ARPGs like Diablo, Grim Dawn etc) so limited mechanics worked well for it.
Divinity Original Sin series however is gunning for cRPG with Turn Based combat. Such a genre where mechanics and tactics both play a huge roll in turn based combat. Just like what we have with games like Age of Decadence, Wasteland series, Blackguards etc. If you oversimplify the mechanics part, theres honestly nothing much to the game then. It is perfectly fine if the devs take down a notch with the mechanics, i'm open to it, but D:OS2 overdid it. You gotta admit the attribute system in D:OS2 currently is as simple as it gets so much so that it is comparable to the system we see in MMORPGs, which as we all know is direct, narrow and shallow. Pretty much a no brainer. You don't even have to bat an eyelid when distributing your points.
That being said, i do agree it is too late for an overhaul. But it is still plausible for a few tweaks and additions to be made for each attribute.
