It IS impossible to do it all and always has been. But we have been sold the myth that it can be done. This (ducks below parapet) is why one parent used to be at home for a few years, but now all these important parenting tasks have to be be fitted in round work. It clearly cannot be done.
I do think that one parent should be supported to be at home - that this should be accepted as the norm - that their role should be valued in the same way as earning money and pursuing a career.
Things have turned on their head - being a parent is seen as a sideline to the the basic economic role of both men and women. Once upon a time women were seen purely as homemakers and then, quite rightly, their educational and career prospects were improved, and now they are locked into the idea that this is what they MUST do, not simply that this is what they can choose to do.
Women's education has given us choice on the surface, but in fact has only given us hugely burdensome lives that demand more of us than any one person can cope with.
One of my DDs has created a situation where her full time career continues, but her OH works only part time and does all the shopping, cooking, child care, school pick-ups etc. It works fine for them. I do not think it matters which parent does which or how the tasks are shared, but someone has to have a bigger role in supporting the children and the home.
I am probably a bit older than most on here - I am sure you had already surmised that! - and I am looking back from the position of someone whose heath has taken a plummet and feeling sad at watching so many women meeting themselves coming back and feeling guilty that they cannot do justice to either career or home/children at a time when they are fit and well and in the prime of their lives - a time for feeling good, not bad! The sword of Damocles of decrepitude is just around the corner!
I was lucky in that I managed both a career (well actually 2 different ones) by working part time for the critical child years, and my OH played his part by having one day off in the middle of the week. It all made our finances a bit iffy for several years, and yes it has affected my pensions, but it was worth it. We both got time with the children and did not completely sink under the load.
Parental leave assumes that people will return to their careers when it ends - it would be good if the assumption was that that return would incorporate a part time element as of a right and a norm. We ask too much of parents now.
One of the spin-offs of this attitude is that grandparents finish up in a child care role - which is great if that is what they want and they do it well - but it should not be seen as the first option - having a parent at home more should be seen as the first one. That is what most parents want. Pouring government support into paid child care is not necessarily the best option. That same money could support parents to be at home with their children for a period of time.
There is no easy answer, but in order to make parents' lives easier (and thus improve the lives of children) there needs to be a change of norms and expectations.