Just another reason never to trust Canadians.
GIF stands for Graphics Interchange Format. Graphics. Guh. Guh-raphics. Therefore, it's guh-if. There is no discussion. Some people are wrong. They are not invited to the discussion.
The inventor of the GIF taking the opposite stance is irrelevant. It's like Orville Wright claiming "airplanes" are pronounced "Krzyzewski" in 1930. No, the root words are "air" and "planes", so ... get out of here, not-linguist. Your brother, too.
Final Jeopardy has been compromised. Alex Trebek is a person of interest, and he goes straight into my dossier. All of you are nuts.
Let's settle this now. If you had to sign one rapper to a record deal, would you go with Hard G or Soft G? Your profits ride on the decision. Now ask yourself if Trebek knows a damned thing about hip-hop. He would sign Soft G, whose songs would be about picking out carnations and yielding to pedestrians.
Hard G would come with the truth.
There. Proven. GIF is pronounced with a hard G. Although, I must say, I'm kind of sad this discussion is finally over, now that I've proven the other side wrong.