Happiness can just refer to the pleasure we find on a sensory level, but real happiness is related to peace of mind. If we have a calm mind, fear and suspicion are reduced. Fear is a major source of unhappiness.
DeFi is not the same as the 2017 ICO craze. Back then, money was raised on shitcoin white papers written in a coffee shops. DeFi is already live and working in the wild. Billions of dollars are at work earning positive yield. This isn’t hypothetical vaporware, this is real.