That person (Joseph Smith) was the prophet of the LDS organization and set the doctrines and practices, which were implemented throughout the LDS organization.
This same person/prophet is the person responsible, among some others (Brigham Young, Taylor, and so forth), for establishing the doctrines and practices of FLDS organization.
In fact, the FLDS claim that they more closely follow Joseph Smith's prophecies than the compromised LDS (1890 Great Accommodation) do. Do you disagree with the FLDS? If so, why?
I again do not get into the details of the religious discussion. Based on what others have posted here, the FLDS at the compound was actually a much more radical sect than what the FLDS was in the past. First, I have no independent proof of that, just what I read here. Second, being less of a cult is not a defense of the cult. But if the FLDS under it’s current leader is distinguishable from the FLDS of 30 years ago, it seems logical it would be distinguishable from the LDS church of the late 1800s.