In combination with sun light, the carbon taken from air provides the energy that plants need to grow, however plants also need minerals from a healthy soil.
When it comes to food, baseline survival is already taken care of in western countries and we are wasting about one third of the food we produce. It's not food that's the problem, but living space and forever rising health care costs.
But you know what the irony is? We don't know a thing about what constitutes a nutritious healthy diet, as the reductionist science we've been applying is not up for this task. Even more aggravating is that trying to shorten the "raise-crops-feed-cattle-slaughter-get-meat" cycle and do it on an industrial scale (by means of replacing sun's energy with fossil fuels and do it in concentrated operations) is precisely the root cause of many of the problems we find ourselves into.
As meddling with the things we ingest has given us the modern day diseases such as cancer, diabetes, obesity and heart disease, not to mention that we're on the brink of going back to the dark ages due to the upcoming "antibiotics apocalypse".
And yet here you are, hoping that some future 3D printer will synthesize meat out of thin air, instead of fixing the real problems in our society, which is that we consume and waste too much from processes that aren't sustainable. But yeah, 3D printing will save us, seemed to work for Star Trek characters at least. Good luck with that mate.