Richard Eder begins a recent review in the Boston Globe by telling us that
Great novels written in the first person require one of two conditions. In “Moby Dick,” Ishmael is essentially a window, though tinted with metaphysical light.
The other option requires becoming a guide of sorts. To play an active part, to become a participant with one hand while clutching our elbow with the other, it is necessary for character and voice to possess an autonomous savor and thrust. . .Huck Finn triumphs because he is, in himself and beyond what he relates, a figure of such winning crag and sheen.
There are not just "two conditions" that first-person narratives must fulfill. First-person narratives can come in all kinds of flavors and can create whatever conditions they want.
First-person narratives are not "required" to do anything, and it is not "necessary" for "character and voice" to possess any particular qualities. Writers are allowed (or should be allowed) to create whatever kind of character and whatever kind of voice suits their aesthetic purpose. The reader (or reviewer) might not be sympathetic to that purpose, but this does not sanction the reviewer to devise a set of aesthetic rules that conform to his taste and that the book under review is obliged to observe.
Eder might have said that he prefers first-person narrators that are like Ishmael in Moby-Dick or that are like Huck Finn. He might have then said that the particular book under review does not create a narrator similar to those in these two books, and therefore he didn't care for this book. That's a pretty restrictive demand to make of a work of fiction, but at least we would know that this reviewer makes such a demand and could judge his review accordingly.
Eder might also simply have said that indeed he didn't like the narrative voice in this novel and therefore didn't care for the book. He didn't need to issue an edict about the use of first-person narrative in order to convey that opinion.