In the middle ages if you were sick you would have been better off being treated by a local herbalist than a University-trained doctor. Not that the herbalist had any decent theoretical model to work to, but s/he had a few traditional methods that weren't actually lethal, and might have done some good. On the other hand the theory taught at University was completely wrong, but because of the social status of the doctors it was unassailable by mere 'facts'. A good example was bloodletting. I was recently reading about a wounded soldier in the American Civil war being drained of 11 pints of blood (obviously over a period of some days) by the doctors employed to treat him. It's a wonder he recovered.
If we can believe that the human race can get things wrong, I think we have to be alert to it happening again. I really think we are like that patient, being drained of blood until we almost die. It is hard for me to know whether the doctors are ignorant or bad.
I also guess that the alternative economic theories we have available are a bit like the village wise women: the theory might be a bit shonky, but at least it stops the bloodletting and gives the system a chance to right itself. If I really wanted to push the analogy to its extreme I might say that Marxist theories are more like mediaeval surgery: drastic, effective, extremely painful, and if things go on, possibly the only way to preserve life.