Proxy Icons are Hidden in Plain Sight
Nick Heer: The Many Capabilities of Proxy Icons
The proxy icon should not be treated as a secret, hidden feature. It is so much more dignified and capable than that.
I've been using the Mac since 1995, I've been entrenched in the Apple community since around 2004, and hand to my heart, I never ever knew about or saw anyone ever use the proxy icon until Apple hid it in 2020.
I'm not here saying that people like Nick are lying when they say they use it, nor am I suggesting Apple was absolutely correct to hide this icon in the Finder until you hover over it, I just continue to be shocked that this feature went completely unnoticed to a hardcore Mac user like myself for decades.