Earlier quoted context omitted.
>you cannot safely use toddler formula as a replacement for infant formula. This needs to be repeated. Do not swap them. My wife and I were trying to help a family by buying them formula - and we bought the wrong age range. It makes a big difference. Don't do it. On a side note, we are going to donate the formula we can't use to a stranger. So. There's that.
I mean, that makes sense, but on the other hand, I'm pretty sure human breast milk doesn't change composition as a child ages. If it's possible to develop a formula that is "close to human breast milk as possible", the age range really shouldn't matter.
This situation primarily impacts 0 to 4 months olds and secondarily 4 to 6 months old. It's less than ideal fora 6 to 12 month old to use a sub-par diet, but it's much less critical than in a newborn.
Basically, the newborn range is growing so quickly that small deficiency can have huge cascading effects. Old babies are a bit more resilient because they're growing a bit slower (relatively) and have more buffer in their reserves for certain things.
In my opinion, what you're arguing is equivalent to saying "children should be allowed to drink alcohol. If it's safe for adults, it's safe for children".