Obviously, the answer to your somewhat grumpy rhetorical questions is “No”. You’re a serious writer if you decide you’re a serious writer, you’re definitely a serious writer if you quit your job to finish your novel, particularly if you write well and write hard and give it your all. And then keep writing, when the novel’s done.
Writers don’t need Clarion. I never attended a Clarion, although I grew up reading about them - I remember Harlan Ellison talking a lot about Clarions in Again, Dangerous Visions, and Clarion seemed both inspirational and scary then. Most of the writers I know didn’t attend a Clarion. It’s great for squeezing a year or two of writing and learning and growing into six weeks, but it’s certainly not for everyone.
Having taught one Clarion, it certainly didn’t seem elitist, and definitely not “of the worst kind”: many, if not most, of the students were on scholarships of one sort of another (there are a LOT of different Clarion Scholarships) and all of them were making sacrifices in order to be there. The money goes toward 6 weeks of room and full board, paying six visiting writers and keeping the programs going.
The writers who were there were doing it to help give something back: trust me, the paycheck is not large enough to tempt me or George R R Martin or Cory Doctorow into giving up a week of writing.
And attending a Clarion as a student is absolutely no guarantee of success. “How do you know which ones of us will make it?” one of my students asked me, my first day at Clarion.
“The ones who keep writing when this is over will make it,” I said.
That was in 2008. And it’s proved pretty much true.
And you don’t need a Clarion to know that. Some writers really like writers’ groups, some don’t; some writers are happiest alone and typing and would find something like a Clarion hellish; and any writer who is going to make it is going to make it, Clarion or not.
Keep writing. Good luck with your novel. And even more luck with the one after that…