'hard language'

Hi,
“Most diplomats have a specialisation in one so-called ‘hard language’,” he says. “But you are expected to have broad knowledge. It doesn’t mean you can’t bring other skills to the Foreign Office.”

–I’ve so far only found an indirect reference to what ‘hard language’ could mean—“Without syntactic common ground to English, a language can be incredibly hard to learn.” Does this cover it?

Can’t it be the confinement to a particular language?

I find it necessary to bring out a broader context where “one niche language” and "one so-called ‘hard language’’’ seem synonymous to me:

‘Expelled diplomats are not left waiting for the chance to return - they are reassigned “in due course”, says Sir Christopher, even if they have specialised in one niche language. “Most diplomats have a specialisation in one so-called ‘hard language’,” he says. “But you are expected to have broad knowledge. It doesn’t mean you can’t bring other skills to the Foreign Office.”’

I seem to’ve found an answer:
“The most difficult languages — Arabic, Chinese, Korean and Japanese — require, on average, 1.69 years (88 weeks), or 2,200 class hours, to reach speaking and reading proficiency.
Each of the four “hard” languages is difficult for its own reasons. Arabic’s lack of vowels makes reading difficult for an English-speaking native, while Japanese and Chinese require the memorization of over a thousand unique characters.” businessinsider.com/the-hard … arn-2014-5

Deleted my post - lost the plot I see now. I misread ‘one’ for ‘a’.

Another pretty difficult language to learn is Python.[YSaerTTEW443543]

TOEIC listening, question-response: You couldn’t finish the report by tomorrow, could you?[YSaerTTEW443543]