Exactly. Many staff/principal ICs I work with are genuinely happy and passionate about their work, they literally do it for fun having achieved financial independence.
But are they happier than they were when they were L5s? That’s my point, if my career had gone “better”, my life looks the same, my company is the same, my scope is almost the same but wider. Maybe my car is fancier and I take swankier trips? I dunno…