but also because the link used has a bunch of tracking clumsily added, which further complicates scanning the thing. Compare the visual complexity of the QR code for HTTP://INSTAGRAM.COM/USERNAME (all caps is important*) vs the cutesy one the app generates.
I wanted to lampshade the caps part, but more explicitly, the QR code's Instagram link to my profile has igsh=xxxxxxxxxxxxx%3D%3D&utm_source=qr appened to it, where the X's are some tracking id. that tracking id that instafram app forces on people makes the qr code much more complicated (= smaller dots on a bigger qr code) which scans just fine on a iPhone 16 that instagram devs use, but that an 8 year old $50 Android phone isn't going to like as much.