That's when the Explorer and task bar started getting convoluted, hiding things, and becoming abstract instead of concrete. It's done in the spirit of helping newbies of course but it actively harms folks who do understand, as well as crippling the newbies who might learn, to always be dependent.

Also, the transparent effects didn't help anything and look silly in hindsight. They also took out color customization and you couldn't have a dark theme for the next ten years!

Of course the type ahead search in the Start menu was a big improvement, and elevation for security. But as always one step forward, two steps back with modern Windows.