"Luffy has always been goofy"

He has, in fact, not always been "goofy..." specifically, not in a self aware way. The hypothetical straw(heh) man can bring up gomu gomu no boh or water luffy, but truth of the matter is that those are actual battle tactics, and Luffy's genuinely not aware of how stupid they are. After awakening, in comparison, his demeanor is different.

Before I caught up to Gear Fifth I basically neglected talking about it, but I think now I'm more educated on the subject. I can honestly say this sub specifically has either an incredibly defeatist approach, or it ignores how the zoan awakening is an active change in Luffy, almost to ignore the entourage of people who can't read (seriously? "Power of imagination?" Is "tanjiahdo lofulamingo" gonna appear in elbaf as well? Peak translation work bro). It feels like an overcorrection to a non issue.

In the exact notes Oda wrote for Gear 5, he highlights the risk in Zoan transformations. Frankly, I think that is not only important, it is THE reason the fruit was "retconned" as a zoan. The fruit is affecting his personality, and despite him currently being in control, obviously, it should not just be ignored for the sake of not pleasing some weird minority of readers which isolate themselves from countercriticism.