> It's either technical stuff that would be much better served in an article or video format, or else it ends up being vapid hype about new language features or the like.
That's been my experience too, so I've been pleasantly surprised by the Julia podcast (Julia Dispatch). Instead of trying to shoehorn the mechanics of code in a podcast (the way most programming podcasts do), they sidestep the issue by making it a human-to-human conversation that happens to have a programming language as an anchoring point.
A small part of it is the historical angle you mention, the interviewee's journey into the project they're talking about, and the project's own journey from idea to infancy to now.
But the more important part to me is the discussion of the mindset behind the project, the reasons for design choices, and how their views have evolved over time. Even as a mere user, it helps a surprising amount to get insight about the thought processes of Karandeep on the Tidier ecosystem or Tim Holy on developer experience; it makes it easier to predict how things will work, and reason about why they work that way.
The format only takes you part of the way though, IMO, a lot of it also comes to down to just interviewing skill. Most podcasts go one of two ways here too: templated boilerplate questions that repeatedly disrupt the rhythm of the conversation, or direct questions about the guest's answers which end up going too niche for most listeners. Michael Tiemann on JD instead follows up on the answer, but not with a direct question that digs deeper (and goes niche), but in a lateral way that often takes the chat in new interesting directions. I think part of the "secret" here is that he takes a few moments after an answer to collect his thoughts and come up with a question - which is a simple thing a lot of podcast hosts seem scared to do, and so they end up taking one of the two quick-and-easy ways above.
(Sorry for the essay, I've had these thoughts bouncing around in my head ever since I found out I liked the podcast more than I thought I would, and I took this as a chance to organize and write them down.)