This is an excellent question!  I think there are lots of different forces to take into account.  First, with the Affordable Care Act, there is a significant increase the number of people with health insurance.  Additionally, one of the less famous provisions of the ACA is mental health parity.  While the enforcement is still variable, this means that a lot of people who previously had insurance, now have much more robust access to mental health services.  While there is still a major problem in the supply of services, many more people have had the opportunity to be evaluated and to enter treatment if needed.  Overall, this is a very positive development, but it does give the appearance that many more people now have mental health problems.  Previously, many of these folks would stay in the shadows because either they did not know they had mental illness that could be treated or because of stigma.  There is a lot more ground to cover in terms of expanding access to all healthcare, both in terms of insurance and quality services, but the Affordable Care Act has made a difference to millions of people.

Since the economic collapse of 2008 and the ensuing recession, millions of people are facing new and very real external stressors.  While the economy has recovered numerically, many families still have not.  There is a widespread perception or feeling that we are walking on economic thin ice and many of us feel very insecure.  Additionally, these last years have put front and center fears of internal and external terrorism, police brutality, and the rise of xenophobia and racism.  All these factors further add to the very real external stressors we all face.  There are not too many ways people can deal with external stressors.  When we are at our best, we can process these using words and talking with loves ones.  When the stressors exceed our ability to talk about them and process them, they come out in less healthy ways.  Often, these come out in either physical feelings (headaches, backaches, stomach aches, and so on) or as psychiatric problems (depression, anxiety, etc).  At times, the way these manifest can be quite extreme with suicide, violence, and psychotic symptoms.  In the backdrop of all this is the increasing suicide rate among service men and women who fought in our foreign wars.  There is also a devastating heroin epidemic that robs people and families of what coping skills they may have had.  In addition to heroin, there are increasing numbers of methamphetamine, synthetic cannabinoid, and other drug use.  All this leads to the very real impression that people seem to have more mental illness than before.

What is the role of capitalism?  First, the financial crisis of 2008 is a direct result of the greed and destructiveness of the most ruthless section of the capitalist class.  The wars in the Middle East also started as a program of individuals who were primarily interested in growing the energy and armament sector.  Our current drug epidemic can be linked to the marketing practices of big pharma and their influence on healthcare regulators and physician prescribing practices in the widespread use of pain control medications.  As physicians understood the immense negative impact of this and started reducing the use of prescription opiates, millions turned to heroin.  Also, under capitalism, people have a lot less security with jobs, homes, food, and other essential needs.  This adds to the external stressors and taps our innate, but limited coping resources.  The antidote to this is to learn how to build resilient communities where individuals can support each other.  We also need serious investment in public mental health programs to help prevent mental illness and in mental health services to help people who developed mental health problems get better.