I actually hoped they'd crack this nut, because the US could use a better and more diverse rental market than it has in most places, but I'm not exactly surprised that the Wall Street boys failed in their mission to turn rental housing into a lucrative income stream. Property management is hard and doesn't scale very well. Property management of single family detached homes is especially hard.
The point is...this was always going to be a tough project. They obviously just saw it as a spreadsheet. kaching kachunk.