As far as I can tell the specification only demands the code modules (pixels) to be square (which is already often ignored in "aesthetic" QR codes which use e.g

As far as I can tell the specification only demands the code modules (pixels) to be square (which is already often ignored in "aesthetic" QR codes which use e.g. round dots instead) and arranged in a square grid. Not that each grid cell has to be filled completely by the respective module. So this might actually be compliant!