Scaling media when nesting

When I nest footage, the nest seems to treat the footage like a screenshot of the footage rather than using the original footage itself. I.E. if I make a 1080 video from 4k footage and use that extra resolution for zooming and cropping in post, when I nest footage that extra resolution disappears. Here is a screenshot, both are from a high-resolution image when fit to screen, and then zoomed in to %100. On the left side is when done from the timeline directly, the image on the right side is nested and the nested footage was then zoomed in. Clearly, there is loss on the right side. Is there a way (like a "scale from source material") option for nested footage?

I need to "zoom the nest" because when I work with chroma key footage moving and zooming the layers independently is a nightmare trying to maintain the correct posisions and zoom levels relative to each other. Especially if the background is a different aspect ratio than the top layer. So yes I know that I can double click on a nest and work the pieces inside, but not moving the pieces individually is exactly why I nested them in the first place. I am looking for a way to scale from the source material automatically when zooming in on a nested sequence rather than, what seems like, bicubic upscaling from whatever is on the screen as a result of each nested frame. If there is a different better tool to use than nesting all together please point me there. It is just a trick someone pointed out to me as an easier workaround.

Thanks!