All of those help the pronunciation of the "word". I've no clue what OWCA is, but for the others they didn't change the very first letter that's for kinda the most important in the phrase. It's an image file, and they make it impossible to directly and verbally connect to the meaning of GRAPHICAL.

I'm not trying to fire on a hill for a pronunciation of an acronym just for my preference of g instead of j. But the absolute most important word in that phrase is graphical, and therefore the g noise absolutely has to be included and that is that for that argument. You don't kill off the main character for some worse than Scrappy Doo schmuck.

And in what world are gif and jif better or worse sounding than each other for this to even have a point? It's like whoever decided on making this fake j solely intended and only cared about making the meaning of it harder to figure out and less representative of its meaning.

Since this reply is about gif I'm mostly done, but as a quick point, for the other examples-

For SCUBA, I'm pretty sure it's just pronounced wrong because fixing that would mess up the letters if they made it work by English rules (there would need to be 2 "B"s). So the argument comes down to making it an acronym or making a new word inspired by the acronym.

NASA is actually the same thing, with a pretty similar change that would be needed. (but 2 "S"s this time)

If both of these could just add a word their problems would be fixed and everyone would be happy.

CAPTCHA I'm only vaguely aware is an acronym and I'm not looking that up right now for sanity reasons (all these hills exploding in this thread giving me PTSD). So I don't know how I feel about that one yet. But one day I'll get curious and look at it.