I'm pretty sure that whatever Gnome saved with CSDs has been more than offset by the huge Adwaita widgets. It's bloody hilarious, Firefox's menubar is almost as thick as a GTK2 menubar + a relatively thin decoration just because of the huge space around the text. It's great on all the three tablets that can run Gnome and on the super high-DPI touchscreens that I presume its developers are runings. The rest of us plebs, however, have to stare at the bulkiest widgets since the days when the Industrial GTK theme was a thing.

(Certainly, that could be solved with a different them, if a different theme would work for more than three frickin' months...)

It also doesn't help that the menubar-toolbar-titlebar mix works great for full-screen windows, and anything but if you're running several non-maximized windows side by side. It's like someone shoved several small iPads on my desktop.

It's pretty difficult to even make a decent case that window decorations were broken; I find it much, much harder to make a case that this is the proper way to fix it.

Edit: it's also going to be so "fun" to get a desktop where some applications have CSDs and some don't, which is pretty much what we're heading to. Just like back in the days when Xlib and Athena widgets were a thing, I am so totally nostalgic for that.