I don't make expert money Dave, but if you want to endorse that...
Materials are what they are, the practical suit is (essentially) a very sophisticated wetsuit with some armour pieces added. It's going to wrinkle, that's just what real fabric does.
It's also going to pull a person's anatomy around in particular ways. Costume designers are expert at controlling that, in fact clothes designers of any sort learn how to control that, but only as far as materials and biology will allow them to.
CG has no limitations in that way. Physics is something that has to be added and it can be changed. Scotty would be deeply envious!
The biggest difference to the look of the CG version isn't the lack of wrinkles, it's the way the "material" follows the idealised human form, rather than forcing the human to conform to the material's physical properties.
That and the choice to removed the armour and blend things like the holster into her leg etc.
It's likely that the original suit was a compromise that everyone was happy with but that, given the chance to go for exactly what they wanted with no limits, the director jumped at it.
Maybe it was the right choice? But I'm not sure that Scarlett in CG sells more tickets than Scarlett in a weaponised wetsuit?