Does anyone here actually understand why One Piece's total sales are down? It only released 30 or so chapters this year, at bare minimum this is 3 volumes. One Piece was pushing 4 or 5 when it was at the top of its sales.
Also, it being 3rd or lower when it still sells 7+ million between 2-3 volumes means virtually nothing to Shueisha, it still will bank always for them.
Not only this, but once Wano ends and the series starts propelling towards its endgame plot, you know increased hype will generate additional sales, however long that takes (5-10 years).
Aka, One Pieces sales will never put it in jeopardy of being canceled or having any issues releasing properly, it just releases 20-30% slower than it used to now.