First, sorry you are experiencing frustration. I would like to however dig a bit more into what caused that frustration for you. I see you mention Divi and whilst Gutenberg is an iteration on the editor it’s not a site builder right now. Where you expecting more of those type of features? If so, I would love to learn more about what for you would make Gutenberg useful and lass frustrating. The product is being iterated on and knowing insights like this helps do that.
Well, first you feel completely lost when trying to edit an existing site. What you see is completely different from what you get. Everything is squeezed into narrow blocks. You just don’t know how to start and there seem to be no way to control how everything will look in real.