Michael, absolutely true. New writers get dinged all the time by script readers, from those who provide coverage to production execs, for not aligning with screenwriting conventions. That’s why I tell my students, they should feel free to write however their creative instincts lead them, but it must always be in service to the story. If they’re writing a page-long monologue just to be like Tarantino or Sorkin, no. Don’t do that. It must come from the character and the situation. The story rules.
That said, there is a path of least resistance to breaking into Hollywood and that is — in part — staying “within the lines” of expectations of what a screenplay should look like.
Whatever the case, you need to write the hell out of it and create a compelling story feature multidimensional characters.