It looks really interesting! I found using a different aspect ratio (5:4 in my recent case) changes how I view and interact with the computer. It just feels refreshing to use something different after years of 16:9 and 16:10. Your window layout might be different, which may or may not benefit your workflow.

I agree video content might look a little strange unless it was kept on either the top or bottom, and not full screened.

I can't imagine it makes the most sense unless you got two of them side-by-side--though that would depend on the nature of your work. I use a 43" 4k 16:9 monitor and don't use the full height, leaving part of the top and bottom edges empty. Moving your eyes/head that much vertically just doesn't seem very natural or ergonomic.