Quite frankly I'd rather never go out again then have to babysit other people's children in a babysitting circle.
That's your personal choice, then, not a reason to categorically tell other women that having time away from your children is impossible per se.
Besides, it doesn't have to be babysitting: any kind of favour will do. I am currently on holiday knowing that my pets are being looked after by a woman who chooses to do me this favour (which she doesn't mind) in return for years of baby-sitting (which I didn't mind). She would probably have done a lot to avoid baby-sitting my children, but then she didn't have to.
Yes, it took a bit of planning ahead and a level of general neighbourliness that would probably be extremely difficult if you are e.g. suffering from severe depression and/or social anxiety. But that doesn't mean it is out of the reach of every woman with children.
I have also had good results from sending my dh round to help people and then cashing in in the form of other services. Which brings me to the argument of pp, that for women with partners, sexism seems to be the major spanner in the wheel. That I absolutely do believe.
If you have a partner, there should be no reason, beyond the first few months of intense breastfeeding, why you can't have as many nights out as he does.
SN did make life more difficult, but because dh is not a selfish twat it made life more difficult for both of us, not just me. My future, my pension pot, my mental health and chance of recreation was always part of the planning.