I don't dismiss African American poetry. Gorman's "poem" doesn't represent all of that poetry, and I dismiss "The Hill We Climb" and any alleged poem that's written just like it. I don't care what the author's skin colour is or what tradition he or she claims to be writing in.
Finding a poem that sounds like Gorman's doesn't meet the challenge, does it? After all, I'm free to say they both stink. The challenge is to define the difference between prose and poetry such that writings like "The Hill We Climb" can count as poems.
As it happens, neither of the poems you mentioned is close enough to Gorman's. Hughes' poem has some similarities (hopeful, platitudinous abstractions), but it also has lots of concrete images and is focused more on the rhyming scheme. Angelou's poem also has some odd images (dinosaurs, mastodons) and unusual, evocative word choices (sojourn, gloom, bruising, spilling).
There's a continuum that connects prose and poetry. At the extreme end of prose is the bland, bureaucratic, anti-creative communication you find in the military, corporations, and the government. And at the extreme end of poetry is the impenetrable, intimidating, uncompromising, literary language in which no word is used in its original sense, and everything is described with fresh eyes. Reading that kind of poetry would be like reading Finnegan's Wake.
Gorman's poem falls somewhere in the middle, mostly on the prose side of the spectrum, with some superficial poetic aspects. Hers is far from the only one. If there are whole traditions of so-called poetry whose works sound just like "The Hill We Climb," I'm happy to condemn the lot of them on the same grounds. There's plenty of fake, worthless art to go around, not just in poetry but in painting, movies, and so on.
We can call this the difference between craft and art. You can make a painting or a movie, but that doesn't make it art. A nonartistic painting would be an illustration, something that doesn't carry a revelatory message or that isn't accomplished with mastery of the craft.