National anthem is not something sacred, not something handed down by God, like Ten Commandments. It is just a song Canadians decided will be the national anthem.
I don’t see anything wrong with changing it. Societal attitudes have changed considerably since the anthem was adopted. If there is a consensus in adopting an alternate language, I say go for it.
A long time ago, a Conservative minister, Flora McDonald raised the same point; she took objection to the reference to the sons. At that time it went nowhere (though I do remember one radio DJ called on his listeners to phone in with alternatives, and many of them did).
I see nothing wrong in revisiting the issue and seeing if a reasonable alternative can be found.