People on THIS SITE have grown fire ass flower using all these bull shit methods ALONG with everyone else who chooses not to use them. Still growing great weed. I personally do not do anything advertised above. But I won’t judge those who do.
It comes down to a lot of people just being passionate about what they do, and about the product. Not a bad thing.
Probably the KISS method is the best, like in so many areas. The things you've mentioned (flushing, defoliating, 48 hrs) cannot have a meaningful impact or else there would be no discussion: it would simply be done by most people. So, the rational way is to not do any of these things, and instead put the time and effort elsewhere, such as
finally getting out of Silver I in
League of Legends.
KISS is also boring; if you grow as a hobby, you want to make it more interesting, so why not apply the secret sauce that so many people tell you is just snake-oil. Feels good to feel you're right about
something.
People just like fighting about the area they're passionate about. I work in computer engineering, and it's the same over there: endless fights and discussions about things you just can't measure, developers in their trenches playing the game. It can be fun to watch with the correct attitude.