Your reply is not passing my sniff test. Your hype and bias are showing.
It may present more fluent text, but if it doesn't know it's strayed from the source text and you can't tell either (because you don't understand source language) then you'll end up with error-laden pseudo translations. At least with NMT you know the errors are consistent.
I don't know who you know who thinks GPT is ahead, but nobody in the very well funded translation industry has a GPT powered translation engine for the key reason that it's not ready for production. For a human to post edit MT, we're mainly talking fixing broken vocab. You'd never present raw MT to a client. It needs editing. Heavily. To think LLM translation doesn't need editing is either coming from someone not in the industry, or blinded by hype. And the kind of editing issues are more insidious, like those found in voice dictated texts. Homophones aren't flagged by QA software because they are real words. Just like LLMs make real sentences, except when they don't, but good luck detecting that, and editing out the additional meaning it has decided to inject.
Have you tried to run the GPT-4 API on a segmented xliff at all? If the segmentation is bad, and full of tags, GPT4 breaks completely. It tries to close sentences that run across segments, it can't handle tags in-line (the chatgpt interface can, but you can't use that at scale).
It can do some impressive work, don't get me wrong, but I'm not sure how hands-on you've really been if you think it's a solved problem.
Production translation is a non-trivial output. The entire industry hasn't released an LLM solution yet for translation (excepting the rewording mini features). What makes you think you know more than those on the ground? Or have you developed something that's still in stealth?
EDIT: Oh wow, all of your 107 submissions to HN from the 6 months your account has existed, have been about AI and LLMs. I guess I got the hype part right. As for industry knowledge the jury is still out, but this could well be the classic HN "I understand tech so obviously I understand everything" play. Keep us posted!