Joseph is guilty of using his own experience in thinking that what he sees in the world around him is all there is. It is a common mistake but not actually based on anything real. The only real census that I know of that can demonstrate the percentage of Chadish Jews of the Orthodox in America is the census by Dr. Marvin Schick of all day school students in America. If you do the math, the chadish are actually 37.7% of the Orthodox. This study was done in 2013. Even given the current population growth in all segments (the yeshivishe and chabad is also quite high) it will not come close to the 60% assumed by Joseph. My guess is that Joseph is not counting Chabad in his category of Chasidish. You read the entire study here
https://avichai.org/knowledge_base/a-census-of-jewish-day-schools-in-the-united-states-2013-14-2014/
While it is true that there is large population growth in areas such Kiryas Yoel, Williamsburg and Boro Park, my guess is that Joseph has not been to areas outside the Orthodox enclaves he is familiar with. Try visiting
the five towns, Teaneck, Baltimore, Los Angeles, Chicago, South Florida, Cleveland, Far Rockaway, Queens, Atlanta, Detroit, Crown Heights, Silver Spring, etc.
In case you are wondering, yes, Dr. Schick’s study does include ALL the chasidishe yeshivos. He is extremely thorough.