I suspect the game will be optimized for whatever the current generation of the consoles will be at the time of its release, at least that was the case with The Witcher 3. So, higher end PCs can use higher resolution, increase settings like draw distance or the number of background (non-interactable) NPCs, implement some additional effects (GameWorks), and achieve higher frame rate, but the assets are the same as on the consoles. Also, not much effort put into supporting PCs significantly weaker than the consoles (it is possible with TW3, but it may require tweaks not accessible via the game's user interface, and I do not know if things like rendering the 3D world at a low resolution but the HUD and menus still at 1920x1080 are possible). Therefore, I doubt if there would be separate lighting methods for low end PCs like STALKER's static lighting mode, which does indeed increase performance a lot, but it is a PC exclusive game.
Although it is an interesting question what consoles will be on the market when CP2077 releases, perhaps there would already be a newer generation, but with the current ones still in wide use? Would the game still support the original PS4 and XB1, or only the upgraded versions?
Edit: regarding the PC version, I wonder if it would require DirectX 12 (and thus Windows 10), or still support Windows 7 and 8? That is, with the game not releasing in the next 12 months, perhaps not before 2019.