It's subtle, and maybe it's just me, but it def seems to me like Oda's really been turning Luffy's "shonen protag" dials way up lately, to the point of decking him out with a lot of the common frills typical of Naruto types. It feels a bit....uncustomary of Luffy. Even seems like Oda's been slightly changing the way he draws Luffy, giving him "softer," smoother features, e.g. slightly less pronounced eyes; Luffy's big, round mongoloid eyes have long been a staple, but it feels to me like they've been.....shrinking in size lately? Haha.
In an arc revolving around change, deceit, transformation....I think it's just one of many intentional tricks Oda's been pulling to play with readers' expectations, among other things. Even the kinda stuff that's been trying fans' patience, disappointing people...also part of a very long-game, slow-burning plan to not only play with readers predictions, desires, complaints, emotions, attachment and dislike of certain characters, etc...but to explicitly make us aware he's been doing so, and how easy at times at that. It's not even simple trolling...it's Oda's extended treatise on perception, manipulation, and so much more...a study of storytelling as expressed through storytelling...In a way, it even speaks to another, meta story: that of an an author, his work, and the fanbase's continuing interplay and synergetic evolution. A story within a story within a story, complete with audience participation like some improv show.
I don't think it's going to last long. Gonna likely go in the exact opposite direction in several ways. A lot of fans are not going to be pleased, I don't think haha. It's gonna be a long couple months. Funny thing is that a lot of those hating on certain characters may gradually change their tune when they see what's in store. And other readers disappointed with certain things may get pleasantly surprised. Topsy turvy all around.