Huh. Nothing to add regarding your question, but I’d always heard this called ‘Main Character Syndrome’. But it looks like ‘Spotlight Effect’ existed long before…
A little basic training in sneaking about helps alley this a lot, eg. working as a stagehand, competitive hide & seek, wilderness survival. Once you know how easy it is not to be noticed you realize that it's often the default, and getting noticed is the hard part.
Growing up helped a lot. I never feel like everyone is staring at me for no reason anymore. If people are going to stare at me, it is because I am wearing my old-fashioned tweed 3-pieces or something.
I suffer from it. I named it "God" and I use it as a way to improve myself over time, despite being too socially isolated to use others' perceptions as my motivation.