It doesn’t matter what it stands for. That’s not how acronyms work.

You don’t say “yolwa” for “YOLO”
You don’t say “Ah-ih-dees” for “AIDS”
You don’t say “britches” for “BRICS”
You don’t say “sue-knee” for “CUNY” (City University of New York) Etc.

And if you want to argue specifically about G:
You don’t say “Jad” for “GAD” (generalized anxiety disorder)
You don’t say “joes” for “GOES” (Geostationary Operational Environmental Satellite)

It’s not a hill I’m going to die on, I use both pronunciations, but the only argument I’ve ever believed for the proper one is that the creator pronounced it “jif”. https://en.m.wikipedia.org/wiki/GIF#Pronunciation

Now let’s talk about “gibs” you heathens.