First off, welcome to IndieTalk.
Now, onto the stuff all newcomers and wannabes despise….
The entertainment industry is HARD. It's a pyramidal structure that is very hard to climb. I started out in the music biz as a performer, and I managed to do fairly well, becoming musical director for a very prominent oldies act. When arthritis curtailed my performing career I moved into music production as a recording engineer and then sidestepped into audio post. But every step up that pyramid means that the hardworking, connected, talented pool of people gets denser and denser as others with less perseverance, talent and connections fall by the wayside. You have to be VERY talented and quite well connected to even get noticed, and those requirements increase the higher you go.
The biggest obstacle, once you are past the halfway mark, is that more and more decisions are taken out of your hands by those who control the market and the money. The money people most definitely want to earn a profit, and they rely on the marketing people, rightly or wrongly, to help them decide how to to invest their money. That "Hollywood" media machine receives tens of thousands of scripts every year, and most of them come through agents, managers and other connections. Maybe a thousand get far enough for more scrutiny by the powers that be. They will green light maybe a couple of hundred for development each year, and only a few dozen actually get produced.
This is the point that all the "shades" "jades" and "unlikelys" that seem to be annoying you so much. This industry is fornicating HARD. The powers that be don't want to waste their time with what they perceive as an unproven wannabe. This may be an unwelcome perspective to you, but it is also a fact of entertainment life. For now, your script is a personal passion project; it's important to you, but, the brutal truth is, almost no one else cares.
Believe it or not, the people here at IT actually do care. The fact that they are responding to you at all is an indication of that. I have posted over 5,000 times in the past dozen or so years in an attempt to help people improve their sound-for-picture skills. I've been there and done that. All of the folks here who are giving you unwelcome screenplay advice have also been there and done that and are truly trying to help you by ripping away the veil of fantasy to reveal the cold hard reality of what you are facing.
I wish you well.