Kurt Vonnegut writes once and does not re-write. In his book he says he is a "basher". Other people write a quick story haphazardly and then painstakingly correct this first draft. He called these people "swoopers".
Carolyn Jewel, a writer of historicals, wrote one book quickly and almost as fast sold it and then was unsuccessful in publishing three or four subsequent books. She states that she suddenly realized that writing fast was her process.
All these writing books profess to know something that can't be known, how to write. It seems to me that writing is different for those who do it. There is no secret formula, secret handshake, private club, or method.
I find that strangly reassuring and wonderful.
What could be more democratic than writing? It doesn't matter how old you are, what you look like, whether you are black or white or even American at all. Nobody cares about anything other than the quality of the writing. It is a job you can do at home.
If you look at the quotes of famous writers about writing they are as varied as their writing methods.
What is writing?
Writing is whatever it means to you.