Absolutely not. I found many G1s with chew marks and haircuts in the 90s (when they were plentiful in thrift shops) and I also see lots of G3s with haircuts. And remember Sid from Toy Story? Yeah, his antics were based on the memories of the people working on the show, who said they used to blow up G.I. Joes with firecrackers, etc. RIP, "Combat Carl."
Also I don't think it's accurate to say it's 'destruction' in case of kids drawing on toys, etc. I was gentle with my ponies but with my other toys . . . hoooo boy! I cut tail holes in doll clothes so my stuffed animals could wear them, I put eyeshadow in a blond doll's hair (and it never came out) and covered her face with make-up, I painted a bunch of my plastic toy animals black because I was pretending they were doing that scene in 101 Dalmatians where the dogs roll in soot to hide from Cruella.
I don't think I was "being destructive", even if I was interacting with toys in a way that would have made them "damaged" in the eyes of a collector. I was just having fun and relating to my toys in my own way.
Edit: Also the reason we don't see as many ratty G1s on eBay any more is that they are gradually removed from the community and customized. And that it's just not worth it to list a baity Cotton Candy, unless she is in a lot with other bait. No one even wants to pay shipping on a beat-up common pony when they could buy a good condition one for $4. But believe me, there were P-L-E-N-T-Y of ratty, chewed, drawn-on, haircut, you name it, G1s around in the 90s.
I've actually noticed that the other gens don't get pen marks on them as much. I wonder if G1 plastic is easier to write on? G3s often have that slightly shiny/slick plastic and G2s & G4s have harder plastic bodies than G1.