You’re calling bs on a discussion between 2 people’s discussion. Ok.
I’m not a scientist, nor have I seen any studies one way or the other on the subject. But I know what I’ve seen with my eyes. My eyes tell me that plants under natural sunlight in natural conditions grow way taller than I could ever deal with indoors. So it’s nothing particular I’m interested in replicating.
I’m not sure how professionals do it, but I want to veg my plants to desired size as quickly as possible. I don’t know if one way is faster than another, but if I find out, that’s what I’m going to do.