Botched grounding in receptacle junction boxes
The conduit's fine...but that ground wire sure isn't

While a properly installed conduit system provides quite solid grounding performance, the pigtail from the receptacle isn't what I'd call an acceptable level of workmanship by any stretch of the imagination.  I would get a proper 10-32 grounding screw and use it to attach the pigtail to the ground hole in the back of the box if I were in your shoes.