I think you're talking about the flow state, which is fine. The flow state is quite productive and invigorating.
My criticisms of happiness as a goal are more meta. Happiness as contentment is a childish, dishonourable ideal. Who says we should be content with living in a godless, amoral, inhuman universe? Who says we should be content with what we are and with what we're doing as the perpetrators of unfathomable holocausts with our industrial farms and our overfishing fleets? Who says we should be happy about our pollution of the atmosphere and our destruction of ecosystems? Who says consumers have a right to be content with their narcissism and their small-mindedness?
No, we need a more existentially respectable goal in life. Happiness isn't on the cards for enlightened folks.
