Well my parents showed me the Back to the Future movies, when I was 8 or 9 and I was able to handle all those things. Was I a tougher kid than most?
I watched BTTF at around 5 or 6 I think. I was watching stuff like RoboCop and Predator on VHS at 7.
I just think people didn't care much back in the day tbh.
These days everything is analysed and judged, usually before it's even released.
It's like Gremlins creating the PG-13 rating with the MPAA.
Kids were going to see it, getting scared, and the parents freaked out.
Movies of old were just seen at face value.
Who Framed Roger Rabbit... it's got cartoons in it... must be for kids.
Gremlins... set during Christmas and has little critters in it... must be for kids.
RoboCop... it's a robot policeman movie... must be for kids. Hell, RoboCop even had a toyline.
Kids back in the old days... if something was scary or uncomfortable, they'd say so, and not watch that movie again.
I'm one of them. If I didn't like it, meh. I wouldn't watch it again.
Simple.
These days though kids are sappy snowflakes, offended at absolutely anything that's set outside their personal safety bubble... and they take to the internet to voice their opinion as if it actually has any meaning.
Studios though, fear them. A single bad piece of press from one millennial can ruin a movie's returns.