Another thing I want to point out is that this will probably increase performance across the board. Let me explain...
If a game is locked at 30 fps, that lock isn't going to change unless a patch comes out that increases the locked framerate. They have already said for things like Destiny this isn't happening.
Think about Fallout 4 for a second - you know how it drops to ~10 fps when you zoom in with a sniper rifle? Those kind of dips aren't going to be as bad with a faster CPU and GPU.
While having the framerate locked at 30 fps isn't ideal, having a consistent framerate greatly improves gameplay overall. Patches will be welcome, but the hardware update will help everything across the board. I don't put faith in the idea that the existing games were designed in a way that would detect and prevent this kind of performance boost. Especially when it's something that can be controlled with vsync.