Based on my experience in a couple courses a while back, the programming auto-graders were pretty good. Not perfect, your code could presumably be a total tire fire but so long as it produced the right answer it was OK--which is admittedly a good part of the battle.

But, yeah, every peer-reviewed assignment and use of discussion board was awful. This isn't a university where everyone is more or less on at least roughly the same footing with respect to language, educational level, and commitment. At least company certs have to maintain some quality floor if they're going to have some value for employers and therefore of interest to would-be employees. As soon as they become viewed as diploma mill trash they're done.