Mine is the one with no stickers

What is the likelihood of seeing another macbook with no stickers compared to the one with the exact same stickers as yours arranged in the exact same way? I think that should address the issue with your argument.

Mine is the one with the gunk.

It's the one next to my shoes and my wallet.

I think that's how pretty much everybody does it

Though every MacBook has some small details that can be picked up even if "identical"

I usually put my carry on (a rolling bag) and personal item (backpack) on the bookends of other bins/belongings on the belt, s.t. all the bins are between two large, distinctly-mine items. It also makes pointing out the items which are mine to a TSA agent significantly easier.

I live in Europe, you need to put the laptop into a plastic box, with all the cables, etc. It's easy to identify it. I put also personal belongings

Precheck saves that hassle.