How are you defining self esteem? (So many different definitions of it.)
I think the difference with it now (moving away from traditional gender roles) is that there are no clear cut ways to be relevent and demonstrate that you are succeeding at whatever it is you are supposed to be doing.
Generations ago, women felt if the kids were healthy and the house was clean and the meals were served up hot when the husband walked thru the door, she was a good wife and an asset to her family and community.
But that's not enough anymore. Most men don't want that anymore and society doesn't reward it. Now there are all these other things she needs to do to feel a sense of self worth: look like a movie star, compete w/ men at work, climb the corporate ladder, run the McMansion, raise the bratty spoiled kids (w/o grandma and grandpa around to help bc you moved away), fight to keep a marriage together that's statistically likely to end in divorce, etc., opening your own doors and paying for dates and buying your own condoms and calling him first. Making the empowered decision to allow your husband consume porn and making the empowered decision to walk off a good-paying job bc you were asked to make coffee. And being labeled a bad employee bc you're a good mom or a bad mom bc you are a good employee. And being a bad daughter in law bc you did both differently than your mother in law wanted.
Just a lot more stuff than women a century ago had to contend with.