The difference is the ability to bear children and the expectation to do the lioness' share of their care and rearing.
I am a woman and I have never, ever had any issue with achieving equality. I have travelled, developed two professional careers, worked with men and women at their same level, with same opportunities and earning the same as them. In my relationships my partners and I have always been equal (the ones who weren't keen on it were given the boot or adapted pretty quiclkly, because I had the same power as them and did not need them). I am now 49, I am very comfortably, I work wnenever I want and set my fees most of the time, I am planning to spend next year travelling to celebrate my 50th, I have a house, an investment property and lots of savings. I love my life. Oh, and currently I have an amazing partner who is more of a feminist than I am. Longh may it last, but if it doesn't... I'll be perfectly ok.
Why could I "have it all" so "easily"?
There is a simple answer: I never wanted children.
I have zero doubts that my life would have been much less equal if I had had the desire to have children. For starters, pregnancy and birth, even if they go seamlessly well, would have set me back in my career and studies. In the worst case scenario, it could have caused me injuries that I would carry for the rest of my life, and set me back even further. Then childrearing: I could have worked on choosing the perfect partner as much as I wanted, but if my partner changed after the baby was here, of ih he proved to be useless with child rearing, then I would still have to do the lioness' share of the baby's cares, because I wouodn't have the heart to just tell the child: sorry baby, you dad is useless, so I am going to be useless too and let you suffer".
Women don't abandon or neglect our children in the same proportion as men do when they are unhappy, so we feel the need to compensate the child, who never asked to be born, for their useless father. So most women end up having the child living with them and doing the majority of their care while the father pisses off looking for a younger, freer woman (untill she has a baby, where the cycle normally repeats itself). Or even if the father stays home, if he refuses to do his share we don't simply refuse to do ours, because we are painfully aware that now there's another person here who will be the one paying for their parents' uselessness and lack of commitment.
As long as women are the only ones with wombs, and with a maternal instinct that stops them from abandoning/neglecting their own child when things don't go to plan, we will never have true equality.