The great masses of our colored people have themselves desired it. It has made our public school system, however, a double system. It is inevitable that it should often have made the negro schools inferior to the white schools. But the social and educational separation of these races has created the opportunity and the vocation of the negro teacher, the negro physician, the negro lawyer, the negro leader of whatever sort. It has not only preserved the colored leader to the negro masses by preventing the absorption of the best negro life into the life of the stronger race; it has actually created, within thirty years, a representation of negro leadership in commerce, in the professions, in church and school and state, which is worthy of signal honor and of sincere and generous applause. The segregation of the race has thrown its members upon their own powers and has developed the qualities of resourcefulness. The discriminations which they have borne in a measure by reason of their slavery, and which have established the apartness of their group life, are the discriminations which are curing the curse of slavery - an undeveloped initiative - and are creating the noblest of the gifts of freedom, the power of personal and social self dependence. The very process which may have seemed to some like a policy of oppression has in fact resulted in a process of development.
Notice the title of the piece: "The Schools of the People". Progressives still use language like that to this day.
This is on the same plane as Woodrow Wilson, who stated that "Segregation is not humiliating, but a benefit, and ought to be so regarded by you gentlemen.". This is really what the progressives thought back then. And they cherry picked information to make their case.
Unfortunately, I can't find a readable copy online, but Edgar G. Murphy has long been considered a progressive. At the end of his 1909 book "The Basis of Ascendancy", Edward Murphy highlights all of the people, groups, and institutions that gave him praise. At the top of the list - The New York Times.
It should not be assumed that this was just as southern progressive ideal that the northern progressives held in disdain, as the link above demonstrates, Murphy was widely praised. And to this day, Woodrow Wilson is routinely and consistently ranked as one of the best presidents we've ever had.