For two reasons: 1) it contradicts my lived experience and 2) it contradicts research.

Let's start with money. I used to be poor and now I'm not anymore. I used to have all kinds of anxieties about money, surprise surprise, once I put my nose to the grind, earned more of it, and developed a healthy financial cushion, those anxieties disappeared and I became happier.

My anecdote isn't the only data point, there's research out there which indicates that more money correlates with more happiness (though the effect has diminishing returns once you hit the upper middle class).

There are at least three really big external factors I'm aware of which are correlated to happiness in a big way.

1. Money

2. A supportive network of family and peers

3. Health and fitness

Every time we look we find that as people improve their circumstances in these areas, they report greater happiness and fulfillment in their lives.

I'm not saying that striving for inner peace and all that is necessarily a waste of time. It has its benefits. But frankly I think if you want to be happy you can do a lot worse than busting your hump to sort out the three things I just mentioned. If you're broke, sick and alone, inner peace isn't really a priority. Working on those problems is.