Q In general, do you think the barriers (filters?) to publication for new authors of fiction are working well? (Are they letting the good stuff through, or do you think there are lots of people who have surmounted the barrier of writing and written good stuff but fail to surmount the publishing barriers?)
A I have no way of knowing, really. What your question reminds me of, though, is my having asked a couple of my literature profs at UBC, in the 70s, whether they thought there were important works of fiction that we didn't yet know of. This was greeted with a sort of amazed disgust. Of course there weren't. (Neither they nor I had ever heard of Cormac McCarthy, then, and he'd been published for over a decade.)
Q And, related, how do you see technology helping and harming with this? Charles Stross has written some interesting blog posts on the economics of a writing career in the days of Amazon, for example, that were quite doomy...
A The economics for the majority of writers, in my lifetime, have never been good at all. I suspect I imagined that the science fiction writers I read in the 60s were all doing rather well. Most of them, actually, were just scraping by, and moonlighting at other things. That was why, I'd guess, many of them seemed to write more often than was good for their writing.