This is especially true in cooking. There is like one method for macron because if you mess it up it won't work. But there are loads of debates about 'real Carbonara' because spaghetti with fatty pork (e.g. guanciale, bacon), egg, and cheese (and maybe cream depending on who you ask), maybe black pepper - you can't fail.
I think it's pretty generally applicable. If you think about it, there couldn't be a controversy if one of the options was clearly and demonstrably better than the other.
Even manufactured controversies like 5G crackpots or snake oil cures seems to often revolve around these nebulous long term effects that hover like a mirage right on the precipice of what's testable, hinted at with a generous interpretation of the scientific literature, but never quite rigorously demonstrated.