As a photographer, not being able to delete photos makes Squarespace unwieldy to use. After about a year, all my portfolio images get updated. It's a hassle to scroll through old photos I'll never use again. I may have a logo from years ago that I need to find, but it's buried in back of the unused images.
At this point, it would be easier to find a new host and build a new site.
This is an issue that needs to get fixed.