I have never known Paypal to be a company that improves their software. This may be the first rewrite since the 90s for all I know. Yes they have a business, but as a consumer and merchant on Paypal the overriding feeling I have always gotten is that they are on cruise control as far as engineering.

So when they say they changed to node and things got better, I just take it as, OMG, paypal tried to improved something and it improved.

Im sure it has nothing to do with node.