Oh the Apple watch system is definitely nice! And I prefer it to having to fiddle around with small pins to shim my watch band off. But that's not so much the issue, the rather odd idea of "hardly anyone changing watch bands before Apple" is.
What probably is true is that pre-Swatch (and maybe some other brands/lines), people certainly replaced watch bands. But it was more because the band was worn out as opposed to casually swapping them for fashion reasons.