My belief was it was significantly bulkier than Gnome when running.
It uses only 0.1GB to 0.2GB of RAM in excess of Gnome. Nothing to talk about.
At run time the RAM use is 3 to 3.2GB of 8GB RAM of my NUC.
What it means is Debian has integrated both Gnome and KDE (Plasma 5) seamlessly.
One can install KDE applications on top of Gnome and Gnome applications on top KDE desktop.
Gnome has Synaptic Package Manager to install Debian applications but KDE does not have a package manager. Instead it probably uses Flatpack to install additional applications.
I had a minor mishap with my Gnome base. I made a mistake while installing KDE on top of Gnome using Synaptic.
I did not select the required dependencies for KDE and Synaptic FROZE and could not use Synaptic.
Even though, both desktops were running OK that was something I did not want to live with.
Not only fresh install of new applications but removal of unwanted applications also hampered when Synaptic is out of place.
.The bottom line is do not try to install several application together. One should install one application at a time. I do install several in one go since I have done it over thousand times BUT I too tend to make mistakes due to laxity of simple principles.
I do not panic since I have three instances of GNOME in my NUC.
Besides I never format my /home partition and it remains intact with all the data.
This is why one should not have one root partition as in UBUNTU install.
I always have /root / boot /home /var and /tmp.
I leave a big chunk of Memory for / var partition and it easily gets chocked.
When that happens reinstall Debian while formatting all partitions except / home.
Previous impression of KDE was based on Netrunner. It took a bit more RAM but Netrunner is a pretty good distribution and I have a copy of it.
I did all this to edit the entry on KDE on my book Linux Essentials. At book level one has to be objective if not scientific.
The book intended to be 100 pages initialy has become 350 pages.
It would be out soon at Amazon Books.