Worthless wisdom & toxic sentimentality

It's so dangerous to indoctrinate children with the belief that life ends when your career starts, and that once your education is over, so are the best years of your life. It sets you up for a lifetime of dissatisfaction, the perpetual inadequacy of adult life leaving behind nothing but the bitter taste of lingering resentment and an impossible desire to turn back time.

To me, working hard and being happy aren't mutually exclusive concepts. My current situation is far from perfect, yet I can still wake up excited for the day ahead. I love what I do. Is that really such a bad thing? And would it be so wrong to teach children to be excited for the future, instead of burdening them unnecessarily with adult struggles and telling them, in all your supposed wisdom, that it's all downhill from there?