It is immoral for all entertainment to be leftwing

I think it's a symptom of the studios no longer making the mid-budget drama or genre movie made for adults.

Those movies not only gave filmmakers a platform to explore their personal sensibilities cinematically, but they also filtered into how other bigger and smaller movies were made. These days the industry only makes incredibly bland and unpersonal franchise movies that are both incredibly militaristic and pro identity politics, or the alternative is tiny budget indie movies that cater to the festival circuit, mostly victim narratives or incomplete experiments...

When you give filmmakers the means to express themselves you're more likely to get a range of thought and emotion, since the better ones will invariably bring their varied personal sensibility to the projects, but if you're just making serialised shows to sell toys then you'll more likely end up with a homogenised product.