My perspective on this comes from almost three years (how is my baby almost three? 
) of grappling with my views on breastfeeding.
I wanted to breastfeed, didn't receive the right support and ended up formula feeding. I became militant about it - breastfeeders were all smug, self-righteous people with their judgypants hoiked high, breastfeeding has no benefits whatsoever, "my child is fine so stick your statistics up your arse" etc.
Through debates on here and learning from posters like tiktok (and even the infamous minifingerz on occasion 
), my views took a big 360 turn, and I realised that the target of my anger shouldn't have been breastfeeding mums, or the act of breastfeeding itself, but the system that failed me in not providing proper support - partly due to being a younger mum - and not signposting me towards other avenues of support.
My daughter has been incredibly healthy. I can count on one hand the number of times she's been poorly, compared to breastfed children I know of the same age who have been ill frequently. She's intelligent - she's been writing her own name for the last few weeks - when breastfed children aren't speaking in full sentences yet. She is my best buddy, we have the most incredible bond.
Do I think that makes breastfeeding obsolete and formula a nutritional equivalent? Of course not. Breastfeeding is tailored to the individual baby; it adapts to their age and their health. Formula is powder in a tub in the supermarket. All this "breast is best", "fed is best" is ridiculous. All of it is bollocks.
Breastmilk is the biological norm. Breastfeeding is something our bodies were designed to do. Sometimes our bodies let us down (mine makes a habit of it 
) and it sucks, but we can't ask science to change because it makes us feel a bit shit. Formula is an excellent invention, marketed by unscrupulous, unethical companies. Information and support is best, regardless of choice.
The way we feed our babies matters, in the same way that whether we babywear or use pushchairs matters, in the same way that whether we send our children to state school or private school matters, in the same way that whether we raise our children as monoglots or multilingual matters. It all has an impact on the person that child becomes, but none of it happens in a vacuum. There is no hard and fast rule that this formula fed child will be poorly and struggle academically, and this breastfed child will be healthy and soar through school.
Genetics, upbringing, family situation, the millions of other choices we have to make as parents all have an impact too - but feeding does matter. Not in the black-and-white way many interpret it, but it does matter.