System76's COSMIC Desktop Working Toward Its Alpha Release

[Mez']

You're mistaking the header bar for a title bar. That is not what it is. This saves space by eliminating the title bar and integrating window controls directly into the application. I'd also add that we will eventually have interface density settings in COSMIC Settings so that you can reduce or increase the amount of padding between elements in libcosmic applications.

Actually, it doesn't save space. It just add a useless extra bar below the DE top bar.
What really saves space are things like Pixel Saver Applet on Budgie or the Unite Extension on Gnome (which mimics what Unity did ahead of its time), where the title bar goes into DE top bar when the window is maximized, then you only have compact menubars visible, and that's what saves vertical space.
Gnome, for example, and CSDs/GTK4 in particular are a total waste of vertical space. Another thing badly designed by their amateur developers.

[Mez']

Thanks for the explanation. I'm also a developer and I totally agree with your vision about C vs Rust.

But I do think GNOME developers have 'special' issues that other C/GTK developers on Linux not necessarily have. Take a look at this article to better understand what I'm trying to say (for those who already read it, sorry for repeating myself): https://medium.com/@fulalas/gnome-me...t-4e301032670c

Excellent article.
This sums up what I've been saying, but whereas I'm not very technical myself, and my opinion of "extinguish" and terrible design was based on impressions, you add some technical examples and blatant Gnome devs misbehaviours.
The Gnome fanboy are sometimes a bit too gullible about the Gnome/GTK community (which is just a fake RH community), and they always whine about why people don't contribute instead of starting something else. Well, this is exactly why. Gnome devs mindset and the very design behind Gnome are total failures.

At the end of the day, contributors who have added value on the desktop vision have no other choice but to go a different path. Who wants to contribute to something they don't believe in or for which your higher-level ideas are consistently rejected?
Canonical back then showed the way as precursors and literally destroyed Gnome with a much superior Unity, then as you mentioned Budgie is distanciating itself as much as possible from the GTK and Mutter bits to eliminate the dependency on moronic Gnome nonsense, and System76 has also witnessed how impossible it is to actually contribute to Gnome in a way that doesn't just produce code (=do their job) for them but actually contributes in terms of design vision, as a proper community should.