Women want to be treated equally and fairly. Up until recent history, women were treated as second class citizens under many laws. Even today, women overwhelmingly face discrimination and harassment in all walks of life, moreso than men.
Nobody wants to work 80 hour weeks. Women's rights is about not having your gender be a basis of disqualification for anything. If a woman wants to work the same miserable demanding job a man works, she should have every right to. Her gender should not be a disqualifier for a job.
Your argument for why wouldn't a mother want to stay at home and be with her kids could just as easily be applied to any father.
Nobody wants to work 80 hour weeks. Women's rights is about not having your gender be a basis of disqualification for anything. If a woman wants to work the same miserable demanding job a man works, she should have every right to. Her gender should not be a disqualifier for a job.
Your argument for why wouldn't a mother want to stay at home and be with her kids could just as easily be applied to any father.