There is plenty of brackets so all can play at their respectives levels, separation in different leagues for collective sports, different levels in individual s

There is plenty of brackets so all can play at their respectives levels, separation in different leagues for collective sports, different levels in individual sports, etc. You can have fun in your local amateur <whatever>, but there would not be any point in a game against professionals. And at the top level, olympics or international competitions, there would be no match in mixed genders for most sports.