'The Google thing' will have told you that Julia Cameron has written forty books, fiction and nonfiction, including her bestselling works on the creative process: The Artist's Way, Walking in This World and Finding Water. Her work has been translated into more than thirty-five languages and has sold more than four million copies worldwide. Also a novelist, playwright, songwriter and poet, she has multiple credits in theatre, film and television. Not just psychobabble, but AFAIK has never claimed that 'it suits everyone', or that 'it always serves any useful purpose'. It is useful to creative people who connect with the practice as an aid to their creativity - maybe less so to others, and no use at all to the closed minded who write it off before trying.
Does anything 'always suit everyone'? Clearly there are people on this thread who find 'it' useful, and writing for one's own benefit or pleasure is never going to harm anyone else. It's not putting others down or dismissing what they enjoy, and will take up half an hour a day of their own time. Does it matter if someone else can't see a useful purpose?