Belonging to the Science Fiction Writers of America (SFWA) isn't trivial for an sf writer -- it's important. SFWA gives the Nebula Awards; it does the Nebula bash and brings out the anthology. It publishes the professional directory, the members-only Forum, and a commercial magazine (the SFWA Bulletin). It has a Grievance Committee that tackles unscrupulous publishers on behalf of members; it does many things that truly matter professionally. Qualifying for membership isn't easy; if you're a science fiction poet, it isn't even possible.
Over the years the question of whether the publication of science fiction in poetry rather than prose should qualify a writer for SFWA has come and gone, with -- so far as I know -- only one brief period when the answer was yes.
This causes a log of cognitive dissonance in many of the members. Saying that sf prose is inherently superior to sf poetry isn't acceptable; saying that the quality of published sf prose is superior to the quality of published sf poetry isn't acceptable. (And can't be demonstrated to be true.) But there's a feeling that something is inherently wrong about accepting three sf poems published at "the standard rate" -- say, $1.00 a line -- as equivalent to three short stories or a novel published at the going rate.
Every time the question comes up, the outcome is that everybody, after endless debate and discussion, throws up their hands in despair and declares that the problem has no solution. How many sf poems does it take to count as equivalent to three short stories or one novel? How can you tell if a poem is as "good" as a short story or a novel? The questions don't even make sense.
I understand the problem. I understand the lack of quality control -- for both prose and poetry. But it's still a form of bias and prejudice to say that you can be a SFWA member only by publishing sf using language that is prose. Meaning that writing "The Tempest" wouldn't have qualified Shakespeare....
I think there's only one solution, and that is for the poetry we sf poets write to be so breathtakingly good, so irresistible to the reader, that SFWA will come to us and ask us for our permission to make sf poetry qualify writers for membership. I don't think we sf poets are focusing hard enough on that standard; I don't think we're working hard enough to achieve it. I don't know how to motivate people to rise to that standard.
It's not fair that this should be the only way to resolve the matter, but it happens with every kind of bias. You have to do far better at whatever it is than would be considered excellent if you weren't part of the population against which the prejudice is directed. SF poets are no exception.