But however controlled you make it, it is an unnatural environment for growing plants. We must assume that there are things missing from the outdoor world which are helpful and healthful, and things present in the indoor world which are harmful, precisely due to the mechanisms by which the environment is controlled or by the fact of the enclosed and controlled space.
Tl;dr - You may control for known things, but you don’t account for the unknowns.
“We must assume...”
No we don’t. Prove it!
In practice, produce grown commercially indoors currently commands premium prices and is sold mostly to high end restaurants — a picky. quality sensitive market.