In my GPT session today the model was convinced Orange and Blue are not the proper fibers for OM4 LC-LC TX/RX, and it could not tell me the correct ones until I told it they actually were and it can check because there's actually a worldwide standard for it.

Gemini on the freaking free tier got it right at the first try.

And this is not the first time I experienced that GPT - on any version - completely got lost, even when the info for the correct answer is widely available on the Web.