I don't see then how that can explain why smarter people are less happy.
In fact if you believe this article, unhappiest people have avg. IQ. Low and high IQ are happy, with >120 being the happiest: https://www.bbc.com/news/health-19659985
In fact if you believe this article, unhappiest people have avg. IQ. Low and high IQ are happy, with >120 being the happiest: https://www.bbc.com/news/health-19659985