Hmm well no, the rules don't change that much. I go through security 2-4 times per week and your liquids still have to be in the bag and your shoes and jackets off.
It's the people who don't empty their pockets despite being told to, who don't carry their ID out even when there's a sign every three feet saying you need your ID and boarding pass, who insist vehemently that hairspray "isn't a liquid, it's a spray" instead of throwing it out and moving forward, and yes, people with kids and strollers who slow the whole thing down.
Those rules don't change. I have been told once in the past four months to leave my jacket on.
I think the confusion comes from the "I'll just do what the person in front of me does" instead of listening to instructions. That person might not remove their laptop because they have a checkpoint bag, or might not take off a belt because they purposefully didn't put it on so as to not have to take it off.
It isn't that complicated but people perpetually act surprised at the process.
There was someone on my last flight who had precheck but didn't even know what a boarding pass is. She couldn't figure out how to use the kiosk to print one, then ran into her again in the precheck Lane where I guess she was lucky not to have to do the shoes/jacket/liquids thing because she didn't know about any of it. Then she couldn't figure out how to board the plane.
Heck, I was behind someone last week in a suit with a Platinum Medallion luggage tag who meticulously removed one item at a time, carefully removed and retied his shoes before placing them on the belt, then went through the scanner with a bunch of papers in his pockets.