I'm 99% sure the creator was either being sarcastic, or he decided to be a contrarian for the internet clicks. "GIF" is an acronym that stands for "Graphics Interchange Format". It makes very little sense to intentionally pronounce it like a peanut butter brand.
Of all the arguments this one always feels like the absolute weakest. There are so many acronyms that are not pronounced like that it's unreal.
Unless you commit to pronouncing it jayfeg for the rest of your life...
actually, gif is an acronym. Specifically not an initialism. That means that it is pronounced as a single word (like "scuba", but unlike "fbi" or "nsa").
The pronunciation of the acronym does not have to conform to the original pronunciation of the letters.
Examples:
the "p" in jpeg stands for the "ph" sound, but we pronounce it as a hard "p".
The "u" in scuba stands for "underwater". We still pronounce it as "scOOba" not "scAAba"
So why is "gif" any different? Its creator chose the soft G for the pronunciation of the acronym (not its expansion), and therefore it is the correct one, simply because there is no rule about how it should be pronounced, so the choice was his. He made it
Yeah not everyone is from the US and had that brand. The soft g has always made sense as much hard g, especially if you say the words Gin or Gym besides it.