script and screen kind of start with the first 3 letters. Scr. for script was in use long before there were screen savers.. Blame MS for using a file extension already in use. But... there is no reason for AutoDesk to continue this practice either.
As I have said before.
The problem here is that the SCR for Autocad was for files for their version for DOS.
When creating a software for the a NEW operating system, Windows, they should have respected the rules fo the NEW environment.
What if someone had decided that .pif was something they had been using in dos so they decided it was OK for them to break every shortcut on your machine when they wrote their windows version?