The contrarian will have established some priority with these once-contrarian ideas, such as being the first to publish on or actively pursue related ideas. And he will be somewhat more familiar with those ideas, having spent years on them.
But the cautious person will be more familiar with standard topics and methods, and so be in a better position to communicate this new area to a standard audience, and to integrate it in with other standard areas. More important to the “powers that be” hoping to establish this new area, this standard person will bring more prestige and resources to this new area.
If the standard guy wins the first few such contests, his advantage can quickly snowball into an overwhelming one. People will prefer to cite his publications as they will be in more prestigious journals, even if they were not quite as creative. Reporters will prefer to quote him, students will prefer to study under him, firms will prefer to hire him as a consultant, and journals will prefer to publish him, as he will be affiliated with more prestigious institutions. And of course the contrarian may have a worse reputation as a “team player.”
See also this old post where Robin Hanson basically predicted that this would happen.