I have read that many critics have been dissatisfied with the modern titling of XXII from Spring and All by William Carlos Williams as "The Red Wheelbarrow". Neil Easterbrook was displeased with the titling because he felt that it set the reader up to read it from a different frame of mind. What did he mean by this?
The new title spoils the minimalist effect of the poem.
Firstly, for reference, the text of the poem itself is simply this:
so much depends
a red wheel
glazed with rain
beside the white
Now, I found the actual article by Neil Easterbrook which you and Wikipedia are referring to. (That link goes to a JSTOR page, where you can't see the full PDF without paying, but I could get hold of it.) The relevant paragraph is as follows (emphasis mine):
Presented within this semantically predetermined package, readers (students) feel the key to the text is held by an initiate authority (the editor or professor), who then dispenses with the text by authorizing a reading. As such, a "self-contained and teachable" fragment is free to be subjected to virtually any sort of interpretative speculation. Treating individual poems like "gears . . . disrelated to the mathematics of the / machine" (P 119), anthologists usually fall back on other than textual or contextual explanations, frequently footnoting one of Williams's infamous dicta-such as "no ideas but in things" (P 9)-in an effort to resolve interpretative dilemmas, even when the "original" context served to leave the dilemma intact and the text suspended between possible solutions. For example, changing the title from "XXII" to "The Red Wheelbarrow" gives the text a specific, specifically different frame. As "The Red Wheelbarrow," even the text's fragmented compound noun is fused into some different thing: literally, its syncretic counterpart becomes a minimalistic poem about a particular object, and figurally, it becomes a gloss on the perceptual horizon, a synecdoche for the pre-problematized experience Husserl called the "natural attitude"16 and Heidegger the "pre-original" or "pre-understanding."17
I have to confess I don't know the meanings of all those words, but what I think this is saying is that the original effect of the poem - its minimalism, its simple beauty - is lost when it's given a real title (rather than just a number), especially one with a four-syllable word in it. As this analysis from the University of Illinois describes the poem (emphasis mine):
No title, without punctuation, minimal diction, tilling rhythm, and modestly internal rhyme (depends/upon, wheel/barrow, beside/white/chickens): it’s not much of a poem, an English formalist might object. What makes it tick? What catches in the eye, cocks the ear? Three modest prepositions—upon, with, beside--place these barnyard minims in visual apposition, or a kind of contingent spatial rhyme, as in Alexander Calder’s counter-gravity-balancing mobiles. Syllable to syllable the ear rolls (wheels) iamb upon trochee, the eye composes (glazes) red with white, as the mind centers (depends) on a barrow beside the chickens. It’s elemental—a figure / ground design scanned in twenty-two slim syllables.
By giving the poem a proper title, rather than its original "XXII", some of this "elementary" nature is lost. This is what the critics feel spoils the intended effect of the poem.