"The airlines" are all very different entities. Each recruitment phase will normally follow a profile that sets a minimum tariff for selection. It is usually a case of whittling down the number of applications until you arrive at a manageable number from which the selection for interviews is made.
Generally the first stage is to set a minimum level of experience required. Nevertheless, that doesn't stop hundreds of applications being received that don't meet this requirement.
If a recruiting airline requires a minimum pass mark in examination scores, then it is free to do that as a means of setting a minimum tariff. Certainly not all do that. It has no correlation to the pass mark required for that particular stage of licence issue. Having a licence means you may meet one of the criteria for employment selection, it doesn't mean you will meet the criteria.
Whatever criteria is set, think of it as a big pyramid. The entire pyramid is comprised of "a pass is a pass." The recruitment team are looking for (what they consider to be) the very apex of the pinnacle of that pyramid.