$21 million for an exhibit on only one side of a controversial issue. It would be the same as opening a pro-abortion museum on the public dime. (Or the same as apologizing to the Japanese for WWII that they did in that exhibit.) I guess it is $21 million of our money not wasted on other things, but it is still wasted.
Controversial? The Theory of Evolution is among the most studied and sound concepts in science. The only people who think it is controversial are either people who don’t understand biology or those who want to push a religious agenda under the guise of science.
It is not a controversial issue.