Hi Mike-
Right now, the image is set to “cover” the available space. This is a special attribute for background images to fill the available space, focus on the center of the image, and respond to different device sizes.
For your requirement of always showing the full image on every device size, I’d recommend switching to a normal image, rather than using a background.
First, use the gray-colored Edit Section > Section Width option to expand the section to full-width:
Then, use the Add Media button to add the image, and select Full Size.