I have to disagree there. FM has the potential for excellent sound quality, and even when massively degraded through the typical commercial station's greed-motivated processing, still offers comparatively good sound.
The digital broadcast as used in the US ... the so-called "HD Radio" ... does not refer to "High Definition". It's just two letters of the alphabet designed to imply a quality that actually doesn't exist. The analog simulcast is higher quality.
Yes, HD stands for Hybrid Digital. I was highly critical of it when it first appeared. It has been greatly improved since introduction. I will say it is at least as good as analog FM now and does have a better S/N ratio.
The big issue for me is LED light bulbs. They emit huge amounts of RF right across the FM band, especially dimmable ones. Here is the noise spectrum of a Feit Dimmable A 19 bulb.
Other brands are similar. I have 150 LED bulbs in this house and most of them on dimmers.
The ones closest to the roof Yagi-Uda array cause the most trouble. Even if the upper level lights are off, I still get some noise if all the lower level great room lights are on. The lower level system only has analog FM. I can use the FM as long as I pay attention to which lights are on.
In the studio I have HD and only use that. Analog FM is no longer usable there.
In our other residence we did a remodel in the spring and added a bunch of BR 30 LEDs. That location is HD only now.
This interference goes a long way. My car has to be a long way from the house before I loose it. I now get it driving down streets in the Twin Cities as more and more people switch to LEDs.
The LED bulb is basically the death knell of analog FM. The RF noise had to go somewhere and I understand the spectrum was selected in consultation with the FCC. So this decision was almost certainly made with malice to hasten the end of analog FM.
I do agree analog FM can sound good, but not as good as other sources. It is not even close to as good as the BBC stream from England, which I get from my VPN tunnel. In fact some of the recordings I made of this year's Proms are among the best recordings I own and better then most CDs. I made some CDs of these Proms for my friend and he says one of those discs is the best recording he now owns. I know of no stream in North America that has that kind of quality however.
In addition to LED troubles we are now used to much wider dynamic range. FM has never had the dynamic range for classical music. The dynamic range on the BBC Proms this year from iPlayer was colossal. In addition FM is limited somewhat on both ends of the frequency spectrum. Digital broadcasting is not. Time to move on.