The Qur'an has two types of verses when giving us rulings.
One is prescriptive, in other words 'do this', do not kill innocents,do not lie, do not take bribes etc.
The other can be termed descriptive, which means do something in particular circumstances, not that you have to do it all the time for all time.
Protectors of women falls into this latter category. If you have women who cannot work, were raised in homes, have children, then men must help them, support them etc. and not think they are weak and undeserving when they, men, go out to work and earn a living; both have a role to play and this cannot be belittled.
When you have women raised up to stand on their feet in society, earn a wage, sometimes more than their husbands, then the protection and maintaining is redundant, does not apply, need not apply.
Old question but I hope this answers it now.