Probably due health problems?
I tell now something which most likely 50% of the fandom thinks but scared to write because of Opla fanbase, we don't need Opla.
Yes the first season was okay, not good not terrible. But we just don't need it. Oda dream in all respect, the Opla team and the dude who is working on it, are amateurs... you can't expect to win the champions league with a fodder team.
Animation and soundtrack been average, actors been average, writing was average..
You can't take a cat and make it to a lion...
It is impossible and Im sad that no one tells Oda this. Or they don't say it on purpose.
Opla start to negative effect the manga if Oda work extra on his free weeks to spend time to work on Opla. I rather have Oda taking two-theee weeks traveling with his family across the world and not spending his freetime to work again with Opla...