This was a recommendation / gift from a prior generation. Now, I don't expect much at all has changed since the 1980's about early childhood development... but a LOT has changed about gender roles in heterosexual relationships (note: LGBTQ+ relationships are DEFINITELY not touched with a ten foot pole so don't be looking for that here, we got plenty of the-mom-feels-this and the-dad-does-that here) and being a woman in the workforce.
I finished the book because along the way there were some interesting/valuable tidbits about the child's development and how to best handle it that seemed useful to know about. But probably you can get that from other books by Brazelton or others that are focused explicitly on the child? To be honest, I also finished the book because it's hard to look away from a train wreck.
Now, I am not a parent (yet) so it is entirely likely that when a baby comes my partner and I, too, will become largely unhinged for a while. This book is laid out as 3 case studies of working parents: one couple with both present but working knowledge white-collar jobs, one single mother by choice, and one couple with both working more blue-collar jobs with the dad away for large swaths of time. To actually relate to any of them I would have to become utterly unable to identify much less address any of my own feelings, toss away all my current ability to communicate with my partner, become deeply personally obsessed with the perceived approval/love of my baby, and lose all current support of my fairly progressive & parent-friendly workplace. I imagine all of this will happen in some degree as sleep goes out the window, maternal hormones kick in, I perform less well at work, etc.... but to me the stories here read like a full on repressed hellscape and I was too busy reading passages out loud in horror to my partner, who listened with amusement mingled with shock, to find almost anything reassuring or applicable. And that's just the personal and interpersonal dynamics described here; the political & legal landscape for parental leave and child care in the US hasn't changed very much from what's described here so the "society needs to step up" is all still very real, but luckily no one at my company has been making disgusting sexist comments to my face since announcing my pregnancy, nor are my coworker parents treated the way the women in this book are.
There's still plenty of feminist fight to go around, so I guess it's nice to be reminded how far our professional and domestic paradigms have come since this was written. I also now have a poster image for the level I never want to reach in erosion of introspection, awareness, partnership, and coping skills.