In my experience ageism is a real factor. So no matter what's on your resume, once they see your grey hair, if you have any left, the negativity kicks in. Of course they won't actually say that, perhaps "too experienced" for the role? Or looking for skills in a trendier area.

Have you confirmed that people actually end up working for that sort of money after a 12 week bootcamp? From what I have heard few companies will pay that much for somebody with only having completed some bootcamp and having minimal track record. It could all be just marketing spin.

Typically if you want to switch into a new field, then not only would you need to learn the applicable technologies, but also get some experience. For example, it is rare that you could pivot your medical device experience to data science and machine learning and keep earning at least the same or more.