I'm a bit more of a realist. If a solution has been given a fair attempt and doesn't work then it's not a solution:

This also includes not relying on any medication to lose weight, which ultimately is avoiding the main issue at hand.

This doesn't achieve the goal. Effectively this boils down to "treat weight gain as a moral failing". Let's assume it is (I don't think it is, but let's just assume it is for the sake of this line of argument) then why haven't we already solved it? The problem persists and is more prevalent than ever.

Taking that approach does not achieve the desired results.

Much like choosing not to look both ways before crossing a one-way street, being in the right doesn't matter if the end result is the same.

I am an existentialist and strongly believe that all people should take responsibility for their lives.

The deck is stacked and people are playing the hands they're dealt. Vast resources have been poured into fucking with people both chemically and psychologically to form poor eating habits, addictions, and limit economic choices. Personal responisbility is of course important but things are a smidge more complex than that.