> Our immune system is dysfunctioning because of something (not natural occurrence)
So, an autoimmune disease? Because that falls within the parameters of what you've described.
> What is that something? - vaccines - toxins, pesticides? - lack of vitamin D, infrared? Something else?
The question of why autoimmune diseases are becoming more common is good one. There is research that shows correlations between the incidence of autoimmune disease and vitamin D deficiency and exposure to microplastics. But as of now, these are just correlations. Causality has not been established, and there are a lot of missing links left on that road.
> Whatever is causing immune problems is at the same time creating a lot of shareholder value.
You give way too much credit to big pharma.
1. We don't know enough about autoimmune disease to know how to intentionally cause it.
2. As with many conspiracy theories, this one relies on the very improbable occurrence of tens of thousands of people keeping mum over multiple decades and not a single one of them growing a conscience at any point. Or just leaking something out of incompetence at any point.