If you Google "how to make homemade baby formula", basically every article is how experts strongly recommend against it. And there are articles like "Why following TikTok influencers' baby formula recipes is a terrible idea."
No shit following TikTok baby formula recipes is a horrible idea. But if a detailed recipe for age-appropriate "standard" baby formula were published by experts, my guess is that it wouldn't contain fairy dust.
I can commiserate somewhat with these "experts", though, because this is a fairly common case where what is good advice for an individual can be bad advice for the masses. That is, if you're a reasonably intelligent person, it's probably not that hard to make your own baby formula. But if, say, at least 20% of people are not reasonably intelligent, experts will err on the side of "lowest common denominator" advice.