That's what I said when I discovered the new GMail look. I felt so uncomfortable with it that I switched back to the old interface. But now that the new interface is the default, I had to look why it looked so ugly, there must be a reason !!
Indeed, there was a good reason, the parameter "Display density" was set to "Comfortable" ("Normal" in French) which has the consequence to have far less emails displayed on the screen than before. I think this parameter did not exist in the past (Anyone can confirm ?), but the standard value for this parameter on the old interface was "Compact" ("Elevé" in French). When you are used to the "Compact" layout it's quiet hard to use the "Comfortable" one, it should be named "Uncomfortable". To conclude I would say that one have to search a little before making early conclusions. So, my apologies mister Google, your new look & feel is not ugly.
PS: Up to now, the old interface is still available is the parameters.