It seems to me that the view that a happy life is just about pleasant experiences is a fantasy. I’m not saying that it is not desirable to have a life full of pleasant experiences, just that a happy life involves more than that.
In his famous thought experiment, Robert Nozick asked readers to imagine an experience machine that would give them any experience they desired. They would be able to select experiences from a large library and the machine would be pre-programmed to give them those experiences while they spent the rest of their lives floating in a tank (Anarchy, State and Utopia, 1971, pp 42-44).
Would you choose to spend the rest of your life hooked up to such a machine?