I've got a couple of points on this topic.
Getting somewhere in entertainment is (approximately) 50% talent and 50% networking, i.e. who you know. People who come from poor families and still make it will, on their way up, have made it their business to meet and ingratiate themselves with powerful people in their chosen profession.
On another issue, the reason why magicians are very poorly represented in the mainstream of entertainment, which pretty much means "on TV", is that a magician has to create a whole new format every time they want a show, so it's a much bigger risk for a production company and/or network. Actors, writers, sportspeople, comedians and so on have pre-existing, proven, TV show formats that they can slot right into. A one-magician magic show stands or falls on the appeal of the central character, the magician, who will, in most cases, be unknown to the general public before their first TV special. There is no room, as there is, for example, with actors, to work your way up the ranks, building up a following before you're given your first starring role. Probably a less risky and more network-friendly format would be a show featuring multiple magicians, hosted by someone already established and recognisable, maybe with a competitive element to it, so magicians were given "magic challenges" with an eventual winner emerging at the end of the show, possibly with a public phone vote. I think in this way, magicians would have the opportunity to showcase not only their magic skills, but their personas, likeability, and, therefore, potential to work well on their own show.