Well MorrisZapp I have to disagree - by all means don't judge others, but you have to remember that humans are mammals, and in order to develop properly we need contact and milk when we are very young.
Humans babies don't regulate their temperature very well, and so need to be with a bigger heat source, and they can't very well forage for fish-fingers in the cold cabinets in the supermarket now can they
So by all means don't judge others, but 'Do What You Like' as a MO is not accurate, or right.
There are ways to ensure that your babe survives, and that their / his /her/ basic biological needs are met: heat; feeding; grooming; their emotional / neurological needs: face to face time and touching.
These basic needs cannot be ignored - you cannot just Do What You Like.
If a mother needs down time, she must factor that in also, but the babe is not the one to pay for it by being left alone without comfort before they are happy to be left alone.
I read those accounts of the Rhesus monkeys with horror when I studied psychology Squiglet. I thought those experiments were so cruel - I don't know if they would be allowed to repeat them, and yet we talk about leaving a babe to cry themselves to sleep without pause for thought it seems.
'Doing what you like' is not best practice if it doesn't take into account that we are talking about baby mammals here.
The first year of a baby's life is such a short period of time in the grand scheme of things, and it's so important in so many ways for human / mammalian development: it's a shame if a mother is not able to be responsive to her babe and meet his /her /their needs, and new mothers often are left alone to do this most important job, which is also a shame, and short sighted.
We need more support for new mothers, and less judgment, but we should also remember that even though we live in an industrialized environment, we are not robots: we are mammals, and mammals have basic needs, all the more so when we are very young.
Leaving baby mammals to cry themselves to sleep for example is totally unheard of in the natural world, and research has shown that those who are left to their own devices at this vulnerable time develop behavioural / social problems later on in life.
Good luck with TTCing MorrisZapp.