I had seen them in museums before 2015… the fact that you specifically didn't manage to work them means nothing.
My symbian phone could read them in 2010.
My symbian phone could read them in 2010.
The running joke for a decade (here in the US anyway) was that nobody had ever actually used one.
iPhones could scan them with the default camera app, but on Android it really depended on the manufacturer.
So you couldn't just say: "point your camera app at the code and open the url that appears.", which made using QR codes pretty much useless unless you had an app where you could build in an scanner for these codes.