How do you get through to Trump supporters who prefer propaganda?

I read an interesting quote today by Evan McMullin:
"I can't stress enough the extent to which Trump's base now lives in an alternative info environment and who can blame them? Everyone is lying to them. Trump. His team. Many right-wing commentators. Congressional Republicans. The GOP. Fox News. This is a huge long-term problem."

Do you agree with Mr. Mcmullin's comment, or do you believe Trump supporters are willfully ignorant?