I am a bootcamp grad who specialized in undergrad in electrical engineering. I worked for a few years as a research for the one of the top tech universities in the country; I have found that I have a stronger math and physics background than many CS grads. However, many times when doing something I have been stopped by saying "wait aren't you a bootcamp grad? can you even understand this?"
I'm not alone; my bootcamp had plenty of STEM majors. One of colleagues was a biomedical engineer and worked in a research lab and now works in the front end at a top firm in SF. Another was a math major at an Ivy before working full stack. The top guy at my bootcamp went to Berkeley in Biochem and was way way smarter than me.
So stop generalizing. I understand that they are unaccredited institution so you get a wide variance of talent but you can't shit on everyone.
To be honest, your issues probably in how you screen talent. My current company has found success in hiring bootcamp and top schools in the area (Berkeley, Stanford).