He went to some sort of "sleep therapist", I forget the exact nomenclature. Anyway, he was recommended a series of tips (from limit screen time to everything else you may see online). He found it did help. That sort of service may be worth looking into.
Have you ruled out alcohol? I’ve heard drinking at night can cause that.
For the over whelming majority of homo-sapiens alcohol tends to increase, not decrease, the propensity to sleep for many hours. Sure there's edge cases but they're rare enough and hard enough to differentiate from other problems that nobody should be trying to diagnose those over the internet.
https://www.webmd.com/sleep-disorders/news/20130118/alcohol-...
Also, you're wildly overestimating what science can do. With many things relating to the human body, it's like we're in the dark ages. For example, tt wasn't that long ago that Chromium was viewed as unnecessary, but now we know that it is essential for regulation of insulin activity.
Also, in term of "breast is best", breastmilk reduces chances of SIDS. Supplementation with formula should probably be used more than it is, but if you want to have the greatest chance that your baby wakes up, use breastmilk if you can.
My wife would spend hours pumping (baby wouldn’t latch) and only produce a few ounces. We always started with that and then supplemented with formula. The kids seem fine.
On the idea of a wetnurse being “gross”, do you drink cows milk? Because that’s basically like having your own cow wetnurse. Sharing milk obviously isn’t for everyone, but don’t dismiss it offhand.
Breat feeding is associated with a (small) difference in IQ: https://onlinelibrary.wiley.com/doi/full/10.1111/apa.13139
Just search breast vs formula milk systematic review on Google scholar and you should be able to find loads of studies.
What you choose to do with that research is entirely up to you.
Another concerning thing with formula is how it’s made. For example, one brand of top shelf organic formula used a chemical known to be a neurotoxin but claim that they remove it all before the manufacturing process is complete, while a competing top brand was using palm oil as one ingredient which is know to be an irritant to newborn’s GI system. So it always felt like choosing the lesser of evils.
There are certainly people who will discourage you from formula. But you have to make your own choice for yourselves and your baby. But frankly neither choice is “bad”.
A part of it was the breast is best craze that has taken over parenting. I don’t disagree with it, but also some people just don’t produce enough milk to fully sustain a child and you need to supplement. When our kids were older my partner found out that her doctor actually noted that her breast tissue was likely to not produce sufficient quantities of milk on her medical chart, but failed to ever tell her. Hence feeding the kids 8-12 times a night, times two kids.
As a result years later I now can’t sleep for more than 5 hours a night without waking up and not being able to go back to sleep for an hour or two. I am slowly figuring out ways to combat this but I have yet to find a solution that lets me sleep a full 7-9 hours my body seems to actually need that doesn’t give me a headache or make my drowsy for the rest of the following day. Sometimes being human is a limitation.