Of course all pop music sounds the same - amm music sounds the asme to the non initiated
The difference with pop music is that, because its created as a commodity it's designed to sound the same

No it wasn't created like that. Elvis and Roy Orbison had voices that were very different - much more different than any two male voices you could find on the British folk scene today. But you don't get that range of voice types today in pop, either. It took decades of evolution for that homogenization to happen.