I use transparency while moving windows all the time, and would like to keep this feature.

FYI This is just a proposed change in default settings, not removing a feature. I'll edit the description to make that more clear.

I have had discussions around this before. I still feel that this doesn't have to be a default but can live with it. If the majority is for changing this default, I can contribute more to the discussion.

I’m against this change, personally. I wish more DEs would use default transparency in 2020.

And many power users when they want to showcase what KDE is capable of, in 9 out of 10 have something translucent on their screens.

Also, as a long time Gnome user, most of us there tried to use hacks to make the windows somehow transparent. It simply was block after block. Boring as hell.

Transparent moving windows also add a bit of ‘detachment’, like ‘I’m not stationary, I’m moving’ feeling to the user.

Permanently visible blurry transparency for windows' background/view areas is something different from the KWin effect that makes windows temporarily transparent while being moved or resized, which is what this task is about.

In T7915#245155, @ngraham wrote:

Permanently visible blurry transparency for windows' background/view areas is something different from the KWin effect that makes windows temporarily transparent while being moved or resized, which is what this task is about.

I know. I just stated my opinion on transparency overall, considering the line "This effect seems a bit gimmicky in 2018 to have turned on by default".

I think it's not gimmicky, not in 2020. It's not something that wobbles or has any cheap animation. That's gimmicky for me. If the user already has something translucent (as most KDE users do), having the temporarily transparent windows while moving is in-line with that.

To be frank, when I just arrived at KDE after years spent in Gnome, moving those windows for me was "oh transparency - finally!". That made me lower the transparency for konsole and menus too! :) Just to put it in perspective. If you guys are all for the removal from default, so be it. But hey, know that some users got hooked on that the first time they saw KDE. ;-)

One thing we have learned over time is that different people have vastly differing definitions of "gimmicky." :)

Personally, I think it's a good effect. It makes it possible to see what's below the window while you're moving it. It's useful because if you just want to see what's below the window, you don't even have to move it out of the way.