Back when they were ongoing;
Fisherman Island was filler and useless.
Dressrossa was shit and dragged way too much.
WCI was utter garbage and one of the worst arcs in OP.
But now, Dressrossa is one of the best arcs in OP. WCI is far better than Wano and Oda was creative af with the devils fruits. FMI at least has a proper plot line with racism and stuff.
You see a pattern here? People never like an arc when it's ongoing due to various reasons. Everything starts making sense only when an arc reaches it's conclusion. There is room to criticize certain aspects of Wano but it's too soon to judge the entire arc.