Came back on site after a couple weeks absence and I noticed that all imagines beyond a certain size are resized by default, regardless of settings. I have show original enabled because I find resizing to be a scourge, but even with it enabled, I still have to click above the image to get it to full size.

In your absence things were changed.

It's still showing the original image. Your browser now scales it to fit horizontally within your viewport, but it is still the original fullsize image.