All of that said, I did not state government programming in my response; rather I used the term "non-profit" programming which could range from public radio to community stations run by non-government organizations to religious outlets. The chance for all of that has long passed but I continue to wonder aloud what the fate of U.S. radio might have been if we had taken, to quote the late M. Scott Peck, "the road less traveled."
We have to consider a societal factor when think about "non-profit" radio operations. For a variety of reasons, the United States and a couple of similarly founded nations has a deep culture of private support for public institutions.
My father was on the founding board of the Cleveland Symphony, and when he taught me business basics (I had a brokerage account at age 9!) he emphasized the need to support civic organizations. He mentioned that, unlike most nations in Europe, "our" symphony orchestras were predominantly privately funded by individuals and corporations. His point is that the private sector has a duty or obligation to give back in ways that create the arts.
Most other nations I've been in for work, ranging from Spain to Pakistan to Bolivia and Colombia, don't have as deep (I have used that term twice now, quite on purpose) a culture of the civic duty to "share the wealth" and contribute to worthy causes.
Perú, for example, has no equivalent of the St. Jude Children's Hospital. There is deeper Church (meaning THE Church in those nations) does some of that, as do a few evangelical Christian faiths. But the dept of public support, even through their churches, is vastly more shallow.
So, even if there were incentives to do public radio offerings neither ad supported nor government financed, it's very unlikely that we would find the funding for a listener supported country or urban or regional Mexican format. Heck, the non-commercial sector has trouble in all but a few markets even doing formats like alternative rock, and even ones like jazz and classical have tough fund raising duties to remain viable in most markets where there is even a station of those types.
What we are getting is a huge variety of paid options for music streaming, many of which are listener customizable. And a million or two talk based podcasts.
The listener is, today, vastly more likely to pay for a streamed service where they have total control over the content and / or a greater variety of programmed "formats". They are not likely to make a monthly contribution to a "community station" for a format that may not be anywhere near as close to what they personally like.
A good example of "failure to support" was the more pop leaning Air1 from the K-Love people. They found that the younger target audience, even if they were "into religion", did not support a program concept aimed at them.