Degree helpful, but not essential
In fact the bulk of pilots who flew for Nigeria Airways in the seventies were trained in Zaria.
They were admitted with "O" Levels in Maths, English, Physics, geog, and another subject (perhaps they did entry exams in addition). They were good pilots, and kept a spotless record until the mismanagement of Nig Airw and frustrations of the larger society caught up with them.
I suppose the refinements of university education can polish the attributes of a pilot, apart from earning him valuable skills. But the truth is, you can become a good pilot without one.
That increasing numbers of Nigerian operators demand one nowadays may be a reflection of the equally increasing number of new pilots asking them for work.