CDE is included as one of the options in Sparky Linux:

https://sparkylinux.org/cde-common-desktop-environment/

For me, it's a bit broken, though; I can't get the terminal to launch, and without that, you can't do much.

I wrote a comparison of CDE and modern recreation NotSoCDE:

https://www.theregister.com/2022/07/28/battle_of_the_retro_d...

A chap I know led the campaign to open-source it and I wrote about it at the time:

https://www.theregister.com/2012/08/09/cde_goes_opensource/