So the Best American Poetry series is not published by Houghton Mifflin, the publisher of Best American Short Stories, among other Bests. BAP is so obviously modeled after the 80s revival of BASS, when BASS instituted a series of guest editors after its longtime editor retired/died (although there remained a series editor who would lighten the burden for each year's famous author/guest editor). It was with BAP's success that Houghton Mifflin realized what a good brand they had going ... and by the late 90s they had started annuals for spiritual writing and science writing and sports writing.
I like the idea of these anthologies. One wants a convenient sampler of recent words. And now one can refine the choice to words on a certain thing. I worked my way through several BASS anthologies back in the 80s (plus some O. Henry Award annuals). When I discovered BAP in its second year I was thrilled as I had very little access to literary magazines in Sebastopol and there was no such thing as the internet. Here was my opportunity to read what was being written NOW. Being a baby poet I wanted to see who my contemporaries (or contemporary elders) were.
I don't think, even then, I was buying the notion that what was contained between any particular Best's covers was objectively the BEST poetry (or whatever) that had seen print that year. I did like the notion that I was being exposed to what that year's famous poet thought great. I've found poems I like in BAP. And poems I don't. BAPs are better than any single issue of your average literary magazine. And you get to know the well-published names.
Houghton Mifflin even registered Best American as a brand. I guess they didn't think of it till after BAP was a going concern at another house. But to anyone who rails about the imprimatur of Best that these anthologies confer I say only: Best American Nonrequired Reading?