"In 2011, James moved over to PayPal, first as vice president of global product development and, beginning in 2012, as chief technology officer. In 2015, he expanded his role to also lead the Payment Services business in PayPal, a global team that powers the efficient movement of money and rewards into, out of, and within the PayPal network."
So, he was CTO/Infrastructure Guy, then they added on SVP Payment Services some time last year, which sounds like it has a lot to do with overall performance.
Shit flows downhill and they needed a scapegoat to make the board happy. The general public doesn't know what a CTO does so problem solved nice and neat.
I would disagree along the lines that the general public didn't even know there was a problem. I'm still not even sure what the issue was, myself(besides the usual complaints about paypal).