I recently moved from KDE to Cinnamon, both using Funtoo and the same configuration. Cinnamon seems to take a lot more memory altogether and I now have to upgrade from 16 to 32 GB RAM to be able to run 2 users (my private and company users). Memory used with the same programs as in KDE consumes around 13GB and once in a while some program dies due to out of memory. With two loged in users the Cinnamon process consumes 1.2 GB RAM by itself.

The main differens between KDE and Cinnamon is how LibreOffice works. It is clumsy and slow in KDE built for KDE and noticeably faster built for GTK in an GTK environment. I am in general quite found of KDE themes but Adwita is the theme for LibreOffice and Inkscape - makes much more sense.
I might even try Funtoo again if I ever have more time to fiddle with my machine - and machines that compile world in less than a week ;) Right now I'm perfectly fine with Slackware's 2-3 year release cycle.
I think it is a beauty that we both can have it our own way even though it differs. That is the spirit of #linux :)
So I got aditional memory (and two M.2 SSDs to run in BTRFS RAID) and now I have 32 GB RAM.
And yet the freaking Cinnamon consumed all the memmory and put the computer down.

I had two loged in users with libreoffice and firefox started. I also had a third instance of Firefox started via sudo (I keep the social stuff in a separate user without access to my real stuff). TO be honest, there was a great amount of tabs started in the social browser and it does not have Java Script Blocker.
I also had a virtualbox with 4GB dedicated RAM started.

In general this is peanuts, yet the bugger consumed all 32 GB and died for me. And no, there is no swap - with that amout of memmory in a desktop it shall not be needed.

I am now back in KDE and this time @Beni Grind I am using Artix Linux that in fact is a packaged linux :)

Right now I have everything excpet for the virtualbox and the huge amount of tabs inm the social browser, consumes 8 GB in KDE.