So I love CSD, but I do agree that the padding, and rounded corners on every element is crap. There is dozens of studies into mistakes / productivity loss when you need to scroll. Programming, accounting, writing etc - everything benefits from more space.
I remember switching from windows to linux for day to day, and finding myself f'king about way more in a debugger to get the info needed (eclipse in this case). Took screenshots in linux and windows... has lost about 20% of screen estate. Horrible.
We've spent decades adding more monitors, and now its all been taken by touch screen garbage.
The sad thing is, GTK and its css classes are probably the best potential for good UI, just the fat finger touch screen requirements has it borderline unusable for a professional desktop.
And the padding. Legit when the corner of a terminal makes the bottom line of text difficult to read, they have gone too far