I think you are the one who might want to think before replying. Opinions are largely what we do here, so when you post something you should expect opinions as replies. Cruise Fanatic's reply to you was not insulting, however your response to CF was.
The facts are that the passport card has limitations that a full passport doesn't have. For closed loop voyages after June 1, a birth certificate and driver's license will still be valid ID...just like a passport card. But neither will cut the mustard for air travel back to the U.S.
Cruise Guru is a karma title based on number of posts, just like Cruise Admiral, or Cruiser. It isn't a title someone gives themselves.
As for Cruise Fanatic's experience...she is one of the most knowledgeable people you will find when it comes to cruises.
As to your question, nobody I know of on this forum has used a passport card for cruise ID. Given the card is a recent development I doubt many of our members even have them, or plan to get them.