The Mac famously had User Interface Guidelines that tried to keep everything consistent. I loved it and, like you, miss it.
But then designers came along and we got drawers (and then we lost the drawers), editable toolbars, brushed metal (and then not), etc...
The point at which I called bullshit was when Safari combined the URL text field with the loading progress bar. I disagreed with the design and said so — it looked to me like the URL was being text-selected as the page loaded. (Ah well, it appears to be gone now anyway.)
But I digress. I had begun to consider that users are now more comfortable with inconsistent UI with the ubiquity of the Web. That has perhaps freed designers to try random stuff on a per-app basis and not adhere so religiously to User Interface Guidelines.
But, yeah, it made life easier for developers too.