Survival of the fittest starts to kick in. It sounds harsh, but that is what happens when there are not means of helping sustain infants that cannot subsist on breast milk alone.
I’m assuming you’re being hyperbolic, but just in case
‘Survival of the fittest’ - in Darwin’s theory - means elements of a species survived bc it had genetic material that allowed it to adapt to a changing environment over 100s/1000s of generations
It certainly does not mean that the most privileged win. Of course we all know that the privileged do win most of the time, but it’s certainly not because they’re ‘fittest’