Progress in packs is weird. I still have a Karimore Jaguar from the early 90s (back when they were made in the UK) that seems to have most modern features you could think of.

It weighs 1600g for a 66L pack which compares pretty well with modern rucksacks too.

I’ve mostly replaced it with a modern OMM Classic 32 trail running pack. At between 430-630g.

Again, that’s a design that originally goes back 1973. I think they got design nailed back then. I haven’t see much in the way of innovation other than slightly better materials.