I can tell you with 100% certainty that not every account owner will be able to tell you this information. Like I said, I've had my gamertag for a LOOONG time - since day 1 of Xbox live.
So that means it could be any one of the dozen addresses I've lived at in the past 15+ years, any one of the credit card #s in the same period (could also be my mother's, since she paid for it when I was a kid), and I have only purchased physical copies of EA games in the past so I'm really clueless on how to look up my history there.
Is there simpler solution than asking a user to dig up decades old information that may or may not exist? Yes. Take 15 seconds to send a verification code to the account (the XBL/PSN account, not the EA email) you're verifying. Account owners will know the code.
Edit: I want to be clear, I am not trying to start a "toxic" discussion. I would however like to share the flaws and frustrations with EA's support and account verification policies. I understand EA community managers can not directly do anything to solve the issue here in this forum but this problem will not magically go away by locking threads. We would like to help EA find a solution that works within their policies as well.