That's been vastly over reported, the default M:F ratio is actually ~1.03-1.05 men to 1 women. Men are however significantly more likely to die every year (other than 10-12), and the age gap at marriage means even more men die before finding a spouse. Add on women are more likely to remarry than men and you can have large gender gaps without destroying society.

PS: China M:F ratio is 106 to 100. By comparison India is 108 to 100 but 90 to 100 over 65 the population is simply young. https://en.wikipedia.org/wiki/List_of_countries_by_sex_ratio