No that is not true, the males will still go at it.
In a good size tank you can keep a bunch of clowns, (fish all from the same clutch that have grown up together is best.) and provided there is enough habitat, and food (more frequent feeding is smart) the fighting should be minimal and spread out enough so that you do not loose too many fish to fighting. The largest will change gender to female, and mate with the most dominate of the remaining males.