I have a grudge against CDE. It superseded OpenLook, which I personally thought was the pinnacle of a clean, professional desktop environment. Some screenshots randomly found on the web:

https://www.deviantart.com/sehnsucht94/art/OPENLOOK-SunOS-li... http://www.martin-graefe.homepage.t-online.de/xview_en.html

I did not only like its look, but also many of its paradigms: That basically everything is started by clicking on the empty desktop, which opens up a menu (you see that menu on the far left in the image); that you can pin menus and other elements to keep them open (even that initial menu mentioned before, it's pinned in the screenshot), that some buttons were "drop down" buttons with multiple actions, and application menus were exactly that (look at the "menu bar" in the File Manager window)...

Meanwhile, CDE is ugly as sin and clunky: https://en.wikipedia.org/wiki/OPEN_LOOK#/media/File:CDE_2012...

Me too but for a different reason. It replaced HP's VUE which had a much 'happier' colour scheme, sans-serif fonts and a nicer-looking 'dock'. HP buried VUE pretty deep after they moved to CDE (which inherited most of the visual design of VUE and some other stuff from the other cooperators IBM and Sun). VUE was what I looked at while studying so it has a strong nostalgic feeling about it for me :) CDE is too different visually to feel 'off'. The colours are too muted and the fonts too traditional. I can see IBM's influence there, VUE was way too 'funky' for them.

https://en.wikipedia.org/wiki/Visual_User_Environment

VUE was never open-sourced sadly and there is no 'remake' of it either like NsCDE: https://github.com/NsCDE/NsCDE

But it's just for nostalgia. I wouldn't use it today. I tried recently (I still own an old HP box with 10.20) but it's just too barebones.