Almost every grower that says defoliation is a must or they are always doing it run a crowded room and or bushy plants. And the growers that say not to do it or the leaves are the solar panels or whatever like space around their plants or have plants with great structure that dont need it.
I say its a tool to be used when needed.
Exactly. Reasons I prune.
1. To keep leaves from stacking creating condensate and ideal conditions for mold or infection and preventing transpiration of said leaves.
2. Remove spindly unproductive growth from the bottom. Usually 1/3 ish of all fan leaves not receiving light and offshoots that I dont want popcorn bud to trim. Not saying this increases yield just that I dont wanna trim that shit.
3. Remove older leaves no long photosynthesizing well. After about 60 days the productivity of a leaf declines. No I can't remember what study I found that info in. But after paying attention I found this to be true.
4. Remove fan leaves that grow towards the inside of the plant as they get less light and restric airflow.
All of this of course is dependant on each plant. Other than lollipoping I do to all for airflow and above mentioned.
Of course this is because I grow indoors. I would not lollipop outdoor plants but rather just any branches close to the ground.