In my view young-earth creationism is exegetically superior and scientifically viable and coherent. It’s possible, however, to err by overemphasizing the issue in a way that demonizes old-earth proponents and lumps them together with theistic evolutionists. The relative importance of something is extraordinarily important, and understatement can be much more convincing than overstatement. Some well-intentioned people use inflammatory rhetoric that overstates the importance of holding to young-earth creationism, and it needlessly pushes people away from the position.
Contrast how Paul Nelson and John Mark Reynolds, who write the essay for young-earth creationism in Three Views on Creation and Evolution (ed. J. P. Moreland and John Mark Reynolds; Counterpoints; Grand Rapids: Zondervan, 1999), conclude their rejoinder (pp. 100–102, emphasis in original):
It is obvious that a person who is generally committed to a traditional understanding of Christianity can be “old earth.” . . . Our disagreements on these points should not distract from the main topic. Philosophical naturalism is retarding science, philosophy, and theology. It seems to both of us that our reviewers agree in finding such a situation intolerable. To fail to unify with such people of goodwill in the assault on naturalism would not just be foolish; it would be intellectual treason. . . .
The key thing is to oppose any sort of attempt to accommodate theism and naturalism. The “theistic naturalism” that results is intellectually impotent and culturally marginal. It apes the language both of traditional religion and science. . . .
Whatever his or her view of Genesis, therefore, the traditional Christian must embrace a robust and plausible theism that dares to test its claims against science and history. We believe that Phillip E. Johnson [a leader in the intelligent design movement] has been instrumental in creating a new way of looking at the old religion and science program. This helpful vision unites the traditionally religious; it does not divide them. It is our hope that old and young earth creationists can set aside their differences to implement that vision.