I have no idea how the parents voted in their State elections, but the people who did vote in Colorado elections knowingly put people in charge who passed this legislation. And every person in Colorado, whether they voted for these people or not, have to deal with the outcomes.
If this particular issue was important to these parents, they could have switched schools, or homeschooled, or moved to a State where there is no such law.
How do you know they could have done those things? Switching schools within the same district might not have made a difference if the policy of concealment was district wide. Not every family can afford private schools. And like it or not not every parent is suited for homeschooling their children. And moving to another state is not as simple as you assume.
These parents and others fighting against policies like this need to be supported not told “Tough nookies you did not do enough to stop it.” Put the blame where it belongs. The teachers and administrators.