You could link to content _in another Stack_ (file) , for that matter. HyperCard absolutely had hyperlinks :) They were just called Buttons, but you could not only directly link to something, but also attach scripting to do additional stuff, pretty much exactly like the <a> tag we use and attach click events to today. I mean, I guess it wasn't like a piece of inline text, but you would just overlay a transparent button. That's a method I used, but there were probably better ways to link text. It was a long time ago, tough to even remember haha
I don't know where you lived but where I did internet adoption was slow, and most computers operated in isolation for years before everyone was connected. Floppy disks and CD-ROM reigned supreme for quite a while. Long enough for a new version of HyperCard to have come out with hyperlink support if that had been a priority.
Yes, good points, but this just shows it wasn't only one thing that made HTML win over hypercard. It did multiple things right, and also was in the right place and the right time to get started. CERN actually had a network that was also used by scientists to exchange documents. Hyperlinks to documents on other computers made sense there. Conquering the desktop in general took a little longer.
the way I remember it, hypercard was hosted locally, as in, you'd get it on a floppy and then copy it to your computer. so linking to another computer didn't really make sense in that pre-Internet era
