What I meant was that if he wants to try out Gnome, he should install only few extensions to have a vanilla experience. Then he can install the extensions he wants. I would have said the same thing for KDE or any DE.
“Try first without tweak and when it’s work and you like it, try modify” something like this.
Okay, let’s compare KDE and Ubuntu, as I understand it.
From what you said, the terminal reminds you than a Pro version exist, and that you can buy it. => This is a ads, they try to sell their product to you.
More question for the Ubuntu parts:
KDE send a notification once a year to say they need donation, help for translation, coding, writing documentation, and more. => This is not a ads, this is a message to get help and donations, and only once a year.
If you don’t see the big difference between the two things, i don’t know how to make it more clear with other words.
I don’t use Ubuntu, and if some parts are wrong, I wait for corrections !