It's shitty to be capped at 30FPS, but DR3 on PC still feels like the definitive version of the game. It's not going to drop frames much if your hardware is good, which is more than the XB1 version can say for itself. And you can uncap it at your own risk, so you don't even need Durante.
The main problem with our engine is that it's custom and in-house but we don't have tons of resources (we make only one game series). And DR3 was developed over a generation transition to boot. All those factors together mean that we can get games out the door and design them mostly how we like, but the code incurs technical debt. So stuff like this happens when something like 60FPS isn't considered in advance, but the engine is too hard to change-- you have to basically rewrite large components, then push out extra QA. I'm guessing the higher-ups don't think PC is enough of a priority for an expensive drive like that. I'd fix it myself, but I get terrified whenever I get into the entrenched code for the core of anything.