Said Rep. Chellie Pingree (D-Maine), quoted in "National parks remove signs about climate, slavery and Japanese detention/The removals come after President Donald Trump issued an executive order in March seeking to remove 'improper partisan ideology' from federal institutions."
You have beautiful places, the best land and rocks and trees and waters of America, and because people want to come see these wonders of nature, you see it as opportunity to interpose human messages — negative, downer messages, propaganda — on eyesore signs. Let visitors think their own thoughts, read their own books, and speak to each other about what they think. That's the better free speech and shared education, not the speech by the government that is installed in the form of inert signs.
Pingree complains that the new policy is "trying to dumb everyone down and... not letting you read a simple sign." But if I'm here for the landscape and the government has put up a political education sign, it's not letting me not see the government's speech.