Hmm rather a medium or simple scene. But this should not affect the absolute difference values. They come primarily from frame buffer allocation (hidden or not).
I found it interesting that with adaptivity+denoising (only beauty pass denoising, if it really comes to pass denoising I hope there will be a checkbox which is off by default you suddenly need approximately twice the ram doing a standard pano rendering. And… adaptivity is for free when denoising is used.