I like to think of mental illness like myopia. Many people used to be blind, but then we figured out the technology, it got cheap, and now 60% of adults wear glasses.
As there is an incentive to classify mental illness for insurance, occupation, and drug development reasons, there is going to be 60% of people on ‘mental illness’ treatment, because we have an ‘ideal human’ (20/20 analogy) that we are trying to reproduce.
As the ideal changes (e.g. homosexuality was thought of in the past as non-ideal, so it was a mental illness, now these things have changed in many parts of the world, so those parts of the world do not classify it as such anymore.), the treatment options/norms change.
tl;dr, it is entirely possible due to biology that eventually ~60% of us will have some classification of mental illness that we will be treated for.
As there is an incentive to classify mental illness for insurance, occupation, and drug development reasons, there is going to be 60% of people on ‘mental illness’ treatment, because we have an ‘ideal human’ (20/20 analogy) that we are trying to reproduce.
As the ideal changes (e.g. homosexuality was thought of in the past as non-ideal, so it was a mental illness, now these things have changed in many parts of the world, so those parts of the world do not classify it as such anymore.), the treatment options/norms change.
tl;dr, it is entirely possible due to biology that eventually ~60% of us will have some classification of mental illness that we will be treated for.