From the perspective of 52 years in broadcasting and still on the air, doing news (at the NPR member station in Sacramento):
Smaller market training grounds dried up in the 80s and 90s. Both stations I worked at in Bishop (population 3,000 1971-74 and 1975-76) had a local news person.
At KIBS it was an experienced guy who'd worked at a smaller station in L.A. after the war, then moved his young family to the High Sierra in the mid-50s. If he got sick, it fell to one of the jocks, which is how I, at 16, wound up asking questions of then-Governor Ronald Reagan about plans to build a highway through the Sierra linking Fresno and Mammoth Lakes (fortunately, he was opposed).
At KIOQ, we hired young people fresh out of Journalism school. They tended to move on at the first opportunity, but that usually coincided with a new batch of grads looking for the door to put their foot in.
In Ukiah (population 10,000 1976-77) and Reno (population 200,000 1977-81), both KUKI and KOLO had two-person news staffs. I don't really remember the background of the Ukiah folks, but I'm betting they'd done at least a year or two in an even smaller town before landing at KUKI. They were quite good.
When I got to KOLO, the ND was a guy named Don Shafer. Total pro. No idea what his background was, but about 90 days after I got there, he went to KCBS. Before long, he was Executive Producer at KRON-TV in San Francisco and I think became Assistant ND before going on to be ND at a TV station in a smaller market. Lost track of him, but I know he was ND in Denver in the 80s for a long stretch and San Diego 10 or so years ago.
His #2, a woman he'd hired straight out of Stanford, hired a guy who'd been working for Ron Jacobs at KPOI in Honolulu...so he had his stuff together. A couple of years later, he went to the CBS-TV affiliate in Reno, I got his job in the KOLO newsroom, and eight months later, I followed him over to Channel 2.
At that time, every radio station in Reno (7 AM, 7 FM) had some news commitment that involved one or more people working as reporters and anchors.
Stan Bunger---the guy who replaced Al Hart in mornings at KCBS in 2000---was working at a South Lake Tahoe station when I was at KOLO (we never met then, but I heard him on the air). And he'd worked at stations in King City and Sonora before he got the Tahoe gig. He did Sacramento and San Jose after that. That's 25 years of experience before he started mornings at KCBS---where he reported for 18 years before they chose him to succeed Al.
The ladders that Stan and I climbed (he went considerably higher than I did) aren't there anymore, with the possible exception of the one common entry on both our resumes, KFBK. Though that's not the same gig as it used to be, either.
Today, hundreds of small-to-medium market radio news gigs where you could make your mistakes and polish your craft are gone. The really small places do local news (and it's often the owner or GM doing it), and after that, with very few exceptions, there's public radio and the big stations like KCBS. It's a huge issue and I don't envy Jen Seelig (KCBS' ND) having to navigate it whenever she has an opening.