* you leave the password in the clipboard, and another website copies it (used to be a thing, I think it's patched now)
* same case, but now a coworker comes to your unattended PC and retrieves the password by pasting it somewhere
* allowing pasting would undermine the idea that you should never write your password down, and lead to a proliferation of files called "passwords.txt" on everybody's desktops
None of this arguments is really good, but I can believe that they would be the result of a world without widespread password managers (also known as "the 90s") and tradition.
* you leave the password in the clipboard, and another website copies it (used to be a thing, I think it's patched now)
* same case, but now a coworker comes to your unattended PC and retrieves the password by pasting it somewhere
* allowing pasting would undermine the idea that you should never write your password down, and lead to a proliferation of files called "passwords.txt" on everybody's desktops
None of this arguments is really good, but I can believe that they would be the result of a world without widespread password managers (also known as "the 90s") and tradition.