I don't know that Faulkner and Hemingway shared the same reasons for writing... Faulkner, near as I can tell, wanted to convey his particular experience and experiences and filled in a lot of 'blanks' to avoid any misinterpretations. Hemingway, on the other hand, wanted to make more of a connection and sculpted his writing to allow for more 'blanks' thus giving the reader permission to insert his/her own experiences and/or perspective into his narrative.

I think that Faulkner allows for some who've not experienced what he has experienced, which expands a notion of humanity. I think Hemingway allows for a shared humanity which is just as potent.

Which is 'better'? I don't actually care to answer that question. Both are valid and should be revered.

Certainly, within the prowess of their own craft, Faulkner and Hemingway are masters.

Why you write is as important as how you write.