People clearly don't know what World Building is:
"Worldbuilding is the process of constructing a world, originally an imaginary one, sometimes associated with a fictional universe. Developing an imaginary setting with coherent qualities such as a history, geography, and ecology is a key task for many science fiction or fantasy writers. Worldbuilding often involves the creation of geography, a backstory, flora, fauna, inhabitants, technology and often if writing speculative fiction, different races. This may include social customs as well as invented languages for the world. " Source: Wikipedia.
One Piece we have Syrup Village, a small village without protection of WG/Marines that a pirate lived many years as a simple employee in order to his master plan to inherit all the money from the sick richest girl. That is World Building.
Baratie a Sea Restaurant that all employees are ex-pirates because they can handle the waves without getting sick and the clients since they are their own protection.
Cocoyasi Village where fishmen uses the sea around them to sink Navy Ships besides all the lore Oda build up about Fishmen explaining why they act like that towards humans(those who were part of Tiger crew).
The whole thing with Reverse Mountain explaining how the 4 seas meet there and how unique grand line is.
Every island has it unique aspect many were briefly showed while others we could explore more.
I'm not 100% aware of Naruto World Building but as far I saw there isn't too much compared to One Piece. HxH is just the same.