This idea has been developed and deployed to Canvas
The new minimum column width causes enormous problems for those of us with many assignments, who shrink the width, manually, to try to see more of the grades.
For example, I have many, many small graded assignments. I have designed the beginning of the names of these assignments to be two or three letters long so I can squeeze the columns as tight as possible and see grade trends for the class at a glance. It will really slow down my workflow to be continually side-scrolling and/or reorganizing columns between "by due date" and "by category" just to see the patterns.
Please restore the capability to manually adjust column width in the gradebook.