I don't disagree with any of that, but I think that it also showcases how the supporting cast in the show is way more developed than the main characters. You're right, they have lives and feel like people who have been doing stuff and happen to have jobs in the industry. That's fine, but that's the setting the protagonists are being thrust into. I feel the weakness in the series that makes it a barrier for people who might not be all that interested in how anime is made, is that the protagonists themselves are extremely shallow and exists as viewpoints and little else. That's not to say it's mechanical or devoid of emotions, just that the point of view feels is somewhat artificial.
Let's distance ourselves from the appeal of how anime is made being presented on the show, and look at the five main characters. The most interesting one by far is the one who has to do a part time job while trying to chase her dreams because she has to make ends meet in the city while trying out for auditions and whatnot. It shows that while she has passion for something, life also makes us try different options. In comparison, what can we really say about the other girls? They're doing basically exactly what they wanted, and there's very little character growth in terms of making them consider what they wanted to do and the reality of what the work is.
I personally don't really see much need for it to deal with "the dark side" of any industry, but it would be nice to have a bit more insight and depth for the lead characters. One thing I remember criticizing the show for is how it handled that movie outing episode when they got together again after a long time. Their reactions were pretty much paper thin expressions of what their character's role in the industry is supposed to be. Are such conversations unusual? Probably not, but given that this is a fictional work, I think it would benefit the characters to be given more depth and interests rather than just being single minded characters representing a discipline in the industry. "The animator girl", "the CG girl", "the production girl", "the voice actress girl", "the writer girl". It's like, sentai writing. Red Ranger, Blue Ranger, Pink Ranger, Yellow Ranger, Black Ranger.
It makes sense from a clean narrative design perspective, but if we're talking about character interactions and dynamics, it would be more interesting if it were a group of friends who might have overlap in disciplines, or might have nothing to do with the industry at all to give an outside perspective. Instead of writer girl being writer girl who is a student and ends up helping to write in anime because they wanted the perspective of someone writing in anime, why not have her be a magazine writer or intern instead? She could be writing about the industry, but not working in it. Why wouldn't there be two or three animator girls instead? How would friends feel if they work in the same line and realize maybe one of them isn't that good compared to the others and she might have to consider doing something different that she is better at. Like maybe illustration or designs rather than animation. The idea of someone trying at something and realizing they're better at someone else instead is not sad or tragic, it's growth.
Like I said, I really like Shirobako, so this isn't me wanting the show to be something else, but pointing out that it could handle certain aspects better and would make it more accessible or appealing to people who want -more- of it outside of just being a dramatized How Anime Is Made show. It wouldn't make it less informative as a Production Drama, but it would add dimensions to the lead characters making them more than just walking POVs for different aspects of the industry.