Yes it is not defined by accounting and finance but those are crucial skills just like learning proper brushstroke is crucial to being a painter. And I disagree that any skill can be taught. Selling, marketing, innovation etc are very dependent on the area of business you’re in, market conditions, the current state of technology etc - too many variables and some skills that are important in one area of business are wrong in a different kind of business, there’s a lot of art to them. Accounting is mostly done one way and the same way whatever your business is and necessary for any business. It makes sense for business schools to teach that first in their core curriculum before teaching things like strategy and marketing. And things like product sense, market timing etc can’t really be taught

Sales and marketing, learned they can be.

A business without knowing accounting/finance, exist can. (An accountant, hire, one can).

For accounting/finance to be useful at all, a business exist, must first.