OK, this is a wild guess, and a bit of amateur sleuthing... but I'm imagining that the 'genius' who came up with these designs is in his mid-twenties, and his first true recollection of a Spurs shirt was this;

....orrrrrr alternatively, he's in his mid-thirties, and the only hazy memory he has of a Spurs kit, are these;


...either way, it's plagiarism!
If you're gonna steal, at least steal something worthwhile having!