I did all of those things too and it did nothing for either my insomnia or depression. There are a surprising number of us out there with, as you say, "actual medical issues".
So you must arguing about his statement about it not being an actual medical condition for the majority? (emphasis added to clarify what I think you're arguing about.)
So it would appear you're challenging him on his statement about population distribution. Your anecdote vs his. While ignoring the condition in his statement.
I think his point was that a lot of people first reach for medicine, when it's often a lifestyle issue.
I didn't see it as belittling those with actual medical conditions.
It's true that some people reach for medicine without trying to change their lifestyles, but I suspect many more reach for the grande coffee or the double shot of espresso in the morning or the beer or wine in the evening. I certainly did my share of that. Nothing wrong with any of those except when they are papering over dissatisfaction with energy level and emotional state. Humans didn't co-evolve with coffee.
1) Always wear socks and semi-tight fitting pants and t-shirt.
2) I increased (yes increased) my calories by ~20% but I stop eating by 6PM.
3) If you suffer from PTSD or wake up screaming when someone tries to wake you, either A) get a dog or B) Do heavy weight training and learn a viscous form of martial arts / street fighting as it will make you feel safer.
4) Avoid toxic people. This one was the hardest.