It certainly depends on the age level you want to coach (for example, college coaches generally played club level or above in college), but it's absolutely not a requisite. Great players don't always make the best coaches, so it's more about understanding the game, having a good coaching track record (i.e. worked with youth, high school, club teams, and continue building -- wins always help....), and finding the right opportunity. Playing in college might help you get a foot in the door (some schools or teams might be more inclined to hire someone with more playing experience), but there are a lot of current coaches who didn't play in college.