That's a clause from the standard GPLv3 covering something different: "An interactive user interface displays “Appropriate Legal Notices” to the extent that it

That's a clause from the standard GPLv3 covering something different: "An interactive user interface displays “Appropriate Legal Notices” to the extent that it includes a convenient and prominently visible feature that (1) displays an appropriate copyright notice, and (2) tells the user that there is no warranty for the work (except to the extent that warranties are provided), that licensees may convey the work under this License, and how to view a copy of this License. If the interface presents a list of user commands or options, such as a menu, a prominent item in the list meets this criterion." The requirement to offer users of modified versions interacting remotely over a computer network a copy of the source is seperate and has no such limitation. Which rather suggests that the drafters of the license considered this issue of requiring people to make unrelated modifications and did nothing to stop it.