Here is an article that lists the social and cultural differences between Finland and the USA and why the USA can’t just import “the Finnish way”.
What we know is, that teaching all children to read with systematic synthetic phonics is the way to bridge the social gaps and get all children reading.
This article also states that where there is little or no literacy experience for young children at home, an early start to learning to read is beneficial.
http://www.shanahanonliteracy.com/2015/10/response-to-joyful-illiterate.html