Does the commenter mean they should have implemented a system to reduce texture resolution or polygon count dynamically, eg. depending on what's in view or how far away it is? That the artists should have made multiple version of assets with coarse variants removing things like computer cables from desks in buildings?
Back in the day, games just had one version of each model, that gets loaded or not.
Nowadays, games with lots of models and huge amount of detail lets each model have multiple different versions, with their own LOD (Level of Detail).
So if you see a tree from far away, it might be 20 vertices because you're far away from it so you wouldn't see the details anyways. But if you're right next to it, it might have 20,000 vertices instead.
It's an optimization technique to not send too much geometry to the GPU.
Basic overview: https://www.youtube.com/watch?v=mIkIMgEVnX0
Or a more detailed one: https://www.youtube.com/watch?v=TwaS5YuTTA0
It's been a standard technique in video games for... decades now.