This is really scary.
I have several systemic diseases/disorders, and several of them have taken many years to diagnose and I have been told many times that my symptoms were "just stress" and in the case of food intolerances they were actually massively improved once I got the right diagnosis and management. It's hard enough to get proper treatment for complex conditions/multiple conditions as it is.

I am also particularly unimpressed with the third bit, which is a perfect example of how we can Never Win, because we're expected to self-manage and 'take control' and responsibility and do healthwork etc but obviously not Too Much.