There's really nothing that I haven't said over and over again for years. Aside from a handful of outliers like WISN, WBEN and WGR (all in markets that skew old and have the kind of very stable populations that remain loyal to an established local station because they've lived there forever, whatever else is left of AM listenership is on an irreversible demographic slide.
All those ratings cited in the musicianslegacy post above? They're all the vanity-show 6+ ratings, and if you have access to the demographic breakdowns, those are all driven by listenership that's now almost entirely 50-plus and largely 60-plus. There's nothing out there showing that younger listeners are aging into an AM radio habit.
Which, once again, means that aside from the perhaps two dozen or so AM stations in large markets that are still producing significant revenue for now (KFI, KNX, WLW, WISN), most of the remaining thousand-plus AMs that don't have translators can't be sold to anyone except the most niche broadcasters, and that's assuming the land under the tower isn't worth more than the value of the license itself.
Even the markets that are exceptions for now, like Buffalo, are just aging out more slowly than the others. If almost nobody under 40 or 45 is listening to WBEN now (and they aren't), that becomes nobody under 50 or 55 before long, and you can't sustain advertiser revenue forever like that, even in Buffalo.