Pre-2001 was... different.
I was stopped by the metal detector at an airport. I didn't know why. Then the guy in the lane next to me said, "Oh, I'm wearing steel-toed boots."
I said, "Oh, I am too." (True)
Without any further questions or checking, they let us both through.
"That? It's just a giant, red, spherical Christmas ornament, with a string to hang it by, that happens to smell of gunpowder... and the monogram 'TNT' on the side."
In ~1997 I got stuck in a huge traffic jam on the way to Heathrow airport. I arrived about 15 mins before my UK->USA flight was to leave. At the check-in desk I handed them my extremely worn passport and the photo just fell out of the back page as they took it. They were like "Er, hold on a sec" and disappeared for a min. Then they came back, handed me the passport and the photo and said "RUN! YOU CAN MAKE IT!" and I did.
Wild times. Planes still had their ashtrays then too.
Yeah, those were different times.
On one of my first flights alone, 16-year-old me had forgotten I had a knife in my backpack. X-ray guy took it with him to a back room, measured the blade to be shorter than, idk, 12 cm or so, and just handed it back.
Another time I found a long wood screw on the floor at school, and out of boredom during class, I just drove it sideways into my boot's heel. Months later it gave the metal detector guys at the airport a bit of a pause. They asked me to remove the boots, x-rayed them, came together to admire my long-forgotten idle work, scratched their heads and had me proceed.
A lot of walkthrough metal detectors will miss metal below ankle height.
I remove mine to send through the xray every time though, even though I'm usually told I don't need to.
I remember pre 9/11 walking right up to the gate my mom was departing out of because she was nervous to go through it. I don't even remember going through security because we didn't have a ticket, they just let us through?
My first time flying myself was a school trip in January 2002, so a lot of the security theater hadn't started yet. There was more security, and I had to remove my jacket and belt, but it was still just a metal detector, and potentially a pat down (saw someone getting pat down).
By the time I was flying a lot for work (2006-2012), it was the full shebang (shoes off, using 3 different bins per person - and waiting for more bins, no jackets, no belts, no hats, no facial expressions as TSA looked at your ID).
Now when I fly it seems like the security takes no time anymore. When I last flew in October, I didn't even give the agent my ticket. Just my passport that they scanned and handed back to me without even looking at me. Same with Customs in the UK and US, scanned my OWN passport, and a gate opened for me to pass through, no border agent or anything.