A Female President doesn't work because voters don't vote for presidents -- they vote for candidates. And even without intending The Importance Of A Female President to dictate voters' decisions, simply deploying it to influence their decisions is a bad idea, because at base it lacks relevance and uniqueness.
It's important that we respect and honor the women who have come before us in this fight. I'm sure it can be frustrating for them to see younger women disagreeing with them about the path to change. But the respect needs to go both ways. Make the effort to listen to and lift up the work of young feminists