No, they can't. The original xbox is struggling with games as is. One of the reasons the slim version has become so popular is because it's extra juice actually allows the games to run pretty decently. A console with half the power of the xbox will not be able to run xbox/ps4 games without a significant time and effort on the part of the developers. There's no possible way to straight-up port the graphically demanding xbox/ps4 games to switch.
I'm not saying this to bash the switch. I just want you to have clear expectations. Games have to be made with switch in mind. Obviously indie games and smaller budget games won't have problems being easily ported but the issue with nintendo consoles has always been about big budget third party titles. And switch won't change that.
