Actually, pretty sure they were talking about movie franchises as far back as the 90s...
contrary to what the horror expert in this entry in the franchise says. She says something along the lines of, these days it's all about the franchises, like it's a recent development.
Of course, movie franchises were around long before that (the Universal Frankenstein movies come to mind), but I'm not sure whether they were being called franchises back then.
I guess you could argue she's young, but she's supposed to be this huge movie buff, especially when it comes to horror.