Currently under PCLinuxOS KDE Plasma 5.27 I have Firefox open with two tabs, Audacious running and playing, and Dolphin file manager, System Settings, Spectacle, and Synaptic Package Manager open - currently 1.51-1.54 Gb!
Oh, nearly forgot, Konsole running htop!
I don't normally have this many apps open anyway, I am not a multitasking user - I believe in K.I.S.S. = no systemd! 