Some say a husband who helps and looks after his wife loses his leadership. Is that true?

Helping and looking after the family is a sign of mature leadership, not a loss of manliness. The Prophet's ﷺ wife was asked what he did at home, and she answered: “He was always in the service of (helping) his family, and when the time for prayer came, he went out to pray” (Sahih al-Bukhari 676). If the best leader of this ummah served his family, such service cannot possibly lower anyone. Take one household task as permanently yours, not just ‘helping’ when asked. Attending to the needs of a tired wife is leadership in the form of action. True strength is using your advantages to lighten the load of others. See responsibilities of husband and wife.