I click the "Use Apple" button and it takes me back at the same page with "you need a valid email account".
This is on the ro.wordpress.com. Maybe it matters.
The problem with Google is that everything is attached to your name. I never write any review on Google knowing that anybody can judge me based on that review alone. Reviews are between me and the target of the review. My coworkers don't need to know what I've bought, where I've been and all my opinions about those things.