Definitely herd mentality on the obligatory, no-cause "defoliation"
https://www.cocoforcannabis.com/community/photons_corner/to-defoliate-or-not-to-defoliate/
Best info in dr photons corner that you can find anywhere. Along with dr. bruce bugbee (apogee instruments) videos on youtube.
Surface area of leaves is the primary factor for yield. Removing leaves that would otehrwise contribute to the end result will only hurt you.
This last grow i purposely bent some leaves over buds at a particular depth in canopy so i could compare it later one... guess what? the buds that were heavily looked exactly the same as all the other buds at that vertical height on the plant.. Apical dominance controls that because the sugars produced from photosynthesis are highly mobile... they are ever-present in the phloem if the plant is fed well, which is piped all over the plant at all times.
too many mouths (method of fertilization/growing will impact this as some are more efficient than others) and too much depth in canopy will cause a higher percentage of larf relative to any parameters set by the genetics.