How about if you only have the ressources to do so much at 1080p, only do so much at 1080p instead of more at lower resolutions? Of course that can only be done for future games, projects like AC Unity started four years ago and they were probably expecting the consoles to be more powerful than they turned out to be. Didn't we all think they'd be better than average to high end laptops? Devs are just trying to deal with that by reducing resolution in order not to throw away 30 % of their assets.