I don't think anyone is confusing you with someone else. You are the only one here that is claiming there isn't sufficient evidence Tesla reads speed limit signs at all, despite people posting evident to the contrary. To be clear, no one here is claiming Tesla is ONLY reading the sign, it is self evidence there is other data given the car has speed limits even without a posted sign.
Evidence refuting your position:
1) Tesla's own wording is quite clear they have the ability to use the cameras specifically (not only map data as previously)
"Speed Assist now leverages your car’s
cameras to detect speed limit signs to improve the accuracy of speed limit data on local roads. Detected speed limit signs will be displayed in the driving visualization and used to set the associated Speed Limit Warning."
Tesla has started pushing a new version of its software update to now visually detect speed limit signs and more....
electrek.co
Video evidence:
You dismissed other examples, but here's one I found just with a couple seconds of Google.
The first few examples where it shows the visualization of existing signs and the posted limit, based on your past arguments, I know you will just dismiss as possible map data.
But at 5:24 he holds up a 45 speed limit sign in a residential zone (presumably 25 mph) where no preexisting sign exists. Not only does it visualize it at the location with a pole, it also changes the detected limit to 45mph. He tries the same spot with a 40mph sign and it changes to 40mph. With both signs next to each other it shows 45mph (he speculates the sign closer to curb takes precedent). How do you explain that other than the camera reading it? It does have memory of the sign as it showed the same 45mph sign when he drove back even though no one is holding up a sign, but in the comments he noted the next day it disappeared.