I'm not sure why pointing to literally geniuses helps us understand how to teach a population how to read. For some people it doesn't matter what method you use. They'll have been taught at home and they will have self-taught the rest.
But, again, what were literacy rates like in 1890 or 1960?
The point is that people before phonics were capable of becoming literate without phonics. The article is saying that phonics is necessary, which is stronger than saying phonics improves literacy rates. If phonics were necessary then people pre-phonics would not have written English literature of all sorts. That is the argument.
In other words:
> For some people it doesn't matter what method you use
This is a theory cop-out. If people figured out how to read and write well without phonics, that's worth investigating too. And it's unlikely that they also succeeded just because they were geniuses or had some secret unknowable method.
Also, replying to someone asking a genuine question with totally different question is bad manners, and I'm going ask that not be done here.
The point of the article is not that teaching phonics is necessary but that the three-cueing system is detrimental to children learning to read. Phonics is a better system.
The article makes the explicit point that significant percentages of children can learn to read despite being sabotaged by a bad learning system. (In part because some students figured out how to spell words out phonetically in their own.)
The formal phonics system might be recent, but the phonetic nature of our writing system is ancient.
But, again, what were literacy rates like in 1890 or 1960?