LOL @ "EVERYTHING NEW IS MARKETING HYPE!!!1!!!!1!!1!"

Pros - 31.8 has removable face plates on the stem making handlebar and stem swaps/adjustments easier (you don't have to unwrap the bar tape and remove the shifters every time you want to change stems.)

Also 31.8 is arguably less flexy/more sturdy although I'm sure someone is going to respond by saying they dropped their quill stem off the empire state building and it survived but a threaded stem broke once and killed their family.