Its a little short sided to think that scumbaggery in Hollywood is limited to the conservatives:
Weinstein Effect
I don't know the political affiliations of all those named in the link, but its fair to say a good chunk, if not the vast majority, are on the left given the historic political leanings of Hollywood.
As a wise man once said, "You will never find a more wretched hive of scum and villany."
Of course I don't think scumbaggery is limited to conservatives. But it has long been conservative actors that have complained that they are not getting jobs because of being conservatives. Which is false as I pointed out a couple big name conservative actors. It is a false cry of victimhood used to deflect the actual reasons they might not be getting work.
The point is scumbaggery, or at least the support for it is a growing requirement of Trump supporters. From the examples I gave look at Kanye, he was a big name in music at one point. But now he is making songs openly praising Hitler. So what studio is willing to risk a $100 million on a film on actors that are potentially going to excuse racism, if not outright support it? It would not be not working with them because they are 'conservative', but because they are likely to show themselves has a horrible person that will cause people to avoid anything they are connected to.