[cfqycwz]

It is true that the use of male pronouns in gender-neutral context has historically been considered correct and is still considered correct by many. It is, however, generally discouraged because it only serves to reinforce the very real and problematic implication of male as the "default" sex.

[okasaki]

Discouraged by whom?

[hyperpape]

It's a fairly common prescription in style guides, though it is still debated: try Googling "style guides gender neutral language" for instance.