If there’s one big reason why even many stupid fans of the show don’t necessarily expect a renewal, it’s the lack of a clear direction for the action.
In the original manga, the protagonist has lost 48 of his organs (for reference, the human body apparently contains about 78, according to WordsSideKick.com), and reclaiming them requires a beautiful epic year-long journey. But in the new show, he only needs 12, which allows the 2019 anime to come to a conclusion faster than the original manga story, which was canceled and got a rather hasty finish.
The new “Dororo” ends the story, but in a way that differs from the original (via Monsters and critics) – it removed a plotline that would have put young Dororo and Hyakkimaru in direct conflict, leaving an open conclusion with a foreshadowing remark from the narrator: “Biwamaru believes that there is more than blood or despair ahead for the two young souls, ” he says.
Should another season come, it may very well choose to go beyond the story embedded in the original manga, and take the characters on new adventures.