Was it explained? There was a comment that Klingons don't like to talk about it but no explanation I remember.
My personal head canon was something went wrong during the DISCO timeline and somehow the process that gave us Tyler ends up infecting the rest of the Klingons who spend the next 50 or so years as swarthy humans before eventually being restored by scientists to the TNG/TOS films ridges we all know and love.
I suspect the bandwidth and storage costs are considerably higher than your average instance as well.