Make sure that Photogrammetry is still turned on within your Data settings. If I recall correctly, if your internet bandwidth drops too low, there will be a message that comes across that asks if you would like to turn off photogrammetry (or it might do it automatically, I can't remember now). So likely it is simply turned off right now in your settings.
I just flew over Louisville, KY in the sim, and the photogrammetry is displayed.