Desktop UIs only started adding that around 2000 or so (Gtk2?), it generally hadn't been possible before in the Windows/Linux world. Even today it still doesn't work as well as the Web, as the select ability is limited to a single widget, e.g. you can't copy&paste the complete text of the About box in Gimp in a single go and many other widget with text don't allow text selection at all.
That said, even on the Web it often feels like an afterthought. What text gets selected when you cross over multiple boxes in a layout often feels completely arbitrary, e.g. dragging the mouse to the left will select text at the top.
That said, even on the Web it often feels like an afterthought. What text gets selected when you cross over multiple boxes in a layout often feels completely arbitrary, e.g. dragging the mouse to the left will select text at the top.