But I think it's tied to how we do business and less a problem which is very specific to the movie industry. Or in other words: it's our fucked up capitalism in action again.
The workhorses of such shows get almost neglected while the shiny poster people and producers get most of the share.
And that's basically everywhere the case. CEOs, managers, superiors are making insanely more money than those who are contributing a lot of work. It's an unfair system which is holding the movie industry tightly in its grip as well.