I agree with what some in the chat said. I think the issue has been, perhaps, lost in translation. Lowering the frame rate is kind of like putting a sticking plaster on a broken leg.
The reason why the resources in use are high is because it renders this in the background.
You can even see the hangar doors closing behind the camera. This is what needs to be addressed, not lowering frame rates as a dev. mode option. Turn off the hangar view entirely.
I imagine this could be an issue if you then click on “My Hangar”, but perhaps not because it gets turned off on the “Content Manager” view.
So my simple proposal is this.
Whatever code turns off the fancy 3D rendered hangar in the background when in “Content Manager”, that causes my GPU usage to drop from 22% to 1%, enable that code on every single menu except the “My Hangar” page.
That is an actual fix, rather than a fudge.
After further playing around, I can see that some trickery is at work. If you actually go to “My Hangar”, and enabled the Developer camera, for a split second you can move the camera, then its locked down. I’m sure this used to be unlocked, which would be a good way to illustrate the problem. You can see this tiny, brief movement of the camera by holding the ALT key down while left mouse dragging even on the main menu.