There is something about slower economic growth that feels "wrong". It seems as if there must be some kind of pathology at work in the economy: a lack of innovation, a failure of policy, an unwillingness to take risks.
But it would be a mistake to jump to that conclusion, because we can be experiencing significant increases in well-being (or welfare, or living standards, or whatever you want to call it) without necessarily experiencing growth in GDP per capita.
The key to improving our well-being is innovation. And yes, one way that innovation improves our well-being is by allowing us to get more — more food, more clothing, more gigabytes, more Netflix shows, more years of life — from the supply of inputs we have. Innovation in this case allows us to turn the same supply of labor, capital, and natural resources into more goods and services, and more goods and services means higher GDP per capita.
But that isn't the only way to take advantage of innovation. There are plenty of examples of how innovation allows us to use less — less labor, less time, less capital, less oil, less fertilizer, less space — of our inputs to produce the same amount as before. Shorter work weeks and longer vacations are absolutely an improvement in our well-being, as are declines in oil use or the acres devoted to agriculture. In this case innovation is allowing us to hold GDP per capita constant while using fewer inputs. And while using fewer inputs to get the same GDP is an improvement in our well-being, it does not involve any growth in GDP.
The point is that growth in GDP is not the only way that innovation can generate improvements in well-being. We've become accustomed to looking at growth in GDP for evidence of innovation and improvements in well-being, and I think that is because in the past it made a lot of sense to use our innovations to "get more" rather than "use less". You don't have to go back very far in history to find large swathes of the population without electricity, running water, or reliable, nutritious diets. In those situations of material need, innovation is naturally going to be used to "get more". More food, more electrical lines (and electricity-using devices), more plumbing, and so on.
But today the vast majority of the population in the U.S. and other advanced economies is well past the point of material need. There is no urgency in expanding our output of food or the availability of material goods like refrigerators, phones, or cars. These things are ubiquitous. Our own preferences have shifted in these situations towards demanding products that "use less", as when we choose to buy locally sourced foods or an electric car. We are now taking advantage of innovation to limit input use, and so stagnation of GDP doesn't represent a failure, but rather a different path towards well-being.