I honestly also think fan portrayals of Luffy (both by people shipping him to other characters or not shipping him to anyone) being so ""childish"" (when he had accepted before Vivi that they cannot save every people in war, & have other displays of maturity I'll mention below... he's just enjoying "stereotylically boyish" things/actively trolling cuz he's so confident in his & his crew's abilities/being indulgent behaviorally most of the time but he is very aware of loss, battle deception, etc.)
that they think he does not know anything about sex or romantic love... is majorly not canon!
Cuz (disclaimer a bit raunchy here) Luffy not only canonically consciously made a balls pun all on his own (the family jewels/kintama ie golden balls thing) in Amazon Lily & *explained* to them that those balls + "mushroom thing" can help make babies (so he knows what procreation is but isn't interested in that at this point in time & all of the main canon One Piece media so far... canon doesn't say he 100% will never want that)
At the start of Whole Cake Luffy also says sth like he knows marrying should only be done out of love & only wants to stop Sanji's marriage if he sees Sanji is not happy with it. Luffy even says he'll invite Sanji's spouse to be part of his crew if they want to! As in Luffy understands what marrying & spouses are, & doesn't oppose having a couple in a happy/healthy romantic/married relationship on his crew & boat at all within canon!
So Oda's words of not having romance on the boat is not absolute- it's just Oda setting the boundary that he wouldn't show romance happening on the boat in the main storyline because his storytelling for the Strawhats specifically would not focus on that, but none of his Strawhat characters have actively opposed to it. Oda even said he knows his characters can be interpretted however his readers want & has long accepted he has no control over that.
Luffy doesn't even call the Strawhats his adoptive family ever in canon! He calls them his friends! He differentiates between them, his friends, from Ace & Sabo who he calls his blood brothers! He never calls Zoro his brother, Nami his sister, etc. (if she is why did Oda not deny he ogled her under Usopp's influence??? Oda said in an SBS it's icky to do that towards siblings, so he'd never make Sanji do that ogling gag to his sister!) Even if Oda says the older guys are like the crew's dads, doesn't mean Luffy himself considers them his actual adoptive dads, for another example less related to this main argument.
So that original poster on Tumblr who recently puts in their z0s4n/one piece/opla post tag that Zolu shippers are in the same category of moral wrongness as incest shippers like Th0rk1 fans can kick rocks,
because the canon they think they're """following properly""" contradicts their own hcs (which they should realize are just personal hcs & not canon representation at all)
literally! just because luffy isnt interested in something doesnt mean he doesnt know what it is or that hes this innocent childlike character bc hes not lol