Yep. I initially looked into it as a potential avenue for sustainably producing some of my own food, but the math absolutely did not make sense.
Growing a bunch of potatoes in a barrel would be a lot more bang for your buck with that goal in mind. To really optimize costs and labor, though, as you say, you need a greenhouse and/or a big old field, just like always. There are no small-scale shortcuts. Not yet, anyway.
It makes me a bit sad that even with modern tech we haven't really made it much easier for people to produce their own food. But it's a reminder that our food production requires large scale collaboration and cooperation. Maybe that's a good thing.
Why are people obsessed with idea of "produce their own X"? When we learned to specialize, we have achieved low cost, scale and sophistication.
There are a lot of cool growing technologies but it’s really hard to beat the sun and rain and soil on cost. Once you go inside you have to provide the medium, the energy via lamps, watering system and all the micro and macro nutrients. Gets more expensive naturally