It all comes down to the doing. Not the talking, nor the planning, nor the dreaming, but the doing. I can see the appeal of being a “pantser”, someone like Stephen King who sits and writes and just churns out reams of text. And he’s a master at that.
When I’ve done that, it’s helped me get a sense of the world I’ve created, the characters, the boundaries of their behaviors, etc., but it takes planning to make sure they don’t veer off into uncharted territory.
But planning can also be overdone.
It all comes down to the doing.
Ideas and plans are a dime a dozen. Writing, and finishing what you start writing, takes persistence and truckloads of discipline.