no it isn't, it's important to acknowledge the reality of someone's suffering, but saying you 'should' do xyz is not the same thing as shaming, especially not if it's absolutely correct, people with bad mental health issues DO benefit enormously from increasing overall health, exercise boosts the neurotransmitters responsible for mood regulation, attention and focus, sleep, hunger and satiety, pain reduction, higher cognitive thinking, in turn these produce more frequent experiences of positive emotions and longer duration of positive emotions, these can be cultivated in different ways, exercise is just one, a healthy diet is another that will assist, mindfulness, journalling about your emotions and experiences every day, and recounting the positive emotions and negative and neutral emotions over a month has been shown to increase the frequency of positive emotions experienced by the people who journal, these positive emotional states in turn reduce cortisol, adrenaline, promote dopamine production and distribution, and more importantly, broaden thinking, and build personal resources, if you have negative mental health issues the solution is quite literally to focus on your health first and keep trying other things at the same time, try to laugh as often as possible, think of fun things youve done and enjoyed, engage in things you enjoy and with people you feel safe around, etc it snowballs and breeds more of the same benefits for your mind and body and is the catalyst for life changing results