The producers who fund these shows will give lip service to "diverse casting" but aren't really doing it for any reason but profits.

Producers who are staring at properties that are relics of nostalgia and plateau on initial demographic need to grow the demographic or they can't afford to up the ante on "pow" to get the current demo enthused.

When someone with money in their pockets says they will give it to you if you serve THEIR interests ... Guess what happens.

If you want to fight "political correctness" in the entertainment business you'll need to convince Hollywood producers that some people's money isn't as desirable as others.

Or that puking out the same formulas and tropes existing fans won't get bored.

"Shaking it up" might not always be a good thing but it gets attention and gets people in the seats to see WTF you just did.

In other words ... If "Political Correctness" is profitable it isn't going away any time soon