In the most important sense a creationist is a person who believes in creation, and that includes people who believe that Genesis is a myth and that creation involved a process called evolution and consumed billions of years.
Most importantly, I agree that the truth of these matters should be determined by interpretation of scientific evidence – experiments, fossil studies and the like.
The monopoly of science in the realm of knowledge explains why evolutionary biologists do not find it meaningful to address the question whether the Darwinian theory is true.
The restriction of religion to private life therefore does not necessarily threaten the vital interests of the majority religion, if there is one, and it protects minority religions from tyranny of the majority.
Some theists in evolutionary science acquiesce to these tacit rules and retain a personal faith while accepting a thoroughly naturalistic picture of physical reality.