As a native (Commonwaelth) english speaker of six decades+ .. it only really "appeared" in frequency during the past decade, more heavily in the past five years or so, in central north American settings.

Grammerly will tell us:

  Despite being more popular than “lessons” in the corporate setting, “learnings” is still incorrect. It's an erroneous plural form of the colloquial term “learning.”

As a business-speak buzz-word it might fade, or it may end up with a greater global footprint outside of the Biz-speak Babel tower.