My retired sister was looking for interesting part time work. She attended a class that promised employment as models and TV/movie extras. Even though it was a university class, it was a scam. The number of such jobs in Tampa was very, very small. There were hundreds of applicants for every opportunity. The politics was disgusting. Right up to and including women and men sleeping with the deciders. I would imagine the same is true universally. This is why you so frequently read that this or that actor is related to other people in the industry. As far as models, for whatever physical type there’s a job for, there are hundreds of qualified applicants. The odds of landing a gig without some sort of “in” are small. Really small.
My Polish girlfriend is an actress for TV advertisements. There would be thousands of women showing up for the casting calls for a simple 5 second ad spot.