This is not entirely true. There were definitely TSRs that would on a keypress save a copy of the screen in a graphics file (or text file for text screens).
I remember using one of these to take screenshots of my favorite games as a kid and save them as GIFs on a floppy disk... Ah, fun times :)
I went looking for old screen capture programs. The first place I checked was simtel (https://archive.org/details/SIMTEL_0692), and found multiple copies of an EGA screen capture program from 1987, such as "CAPTURE.ARC 21504 06-11-87 Screen capture to disk file (from PC Magazine)". There was also an earlier dated file for dumping Hercules screens to Epson printers.
The sibling point about digital prepress is a relevant one too: So you have a file on your computer with the contents of a screen .. whatcha gonna do with it anyway?
Not to be a pedant but I am not sure how a Mac would be able to capture AutoCAD screens running on a PC . AutoCAD for Mac didn’t ship until ‘92.
The AutoCAD business was interesting. So many gadgets like extended memory cards, math coprocessors, crazy video cards. Anything to give a speed up in rendering and processing.
Even if you had a standard image format. Digital prepress for printing was still a decade away. They were still doing print with Celluloid separations, so you would do slides
I remember using one of these to take screenshots of my favorite games as a kid and save them as GIFs on a floppy disk... Ah, fun times :)
The sibling point about digital prepress is a relevant one too: So you have a file on your computer with the contents of a screen .. whatcha gonna do with it anyway?
The AutoCAD business was interesting. So many gadgets like extended memory cards, math coprocessors, crazy video cards. Anything to give a speed up in rendering and processing.
https://en.wikipedia.org/wiki/AutoCAD_version_history