True but you are talking internet streaming competition which is a whole nother thing and really is oranges to apples. The reason being that internet streaming requires an internet subscription which is not something that everyone has, or if they have it in their home, far less have it on their mobile devices. And if they do, then they almost certainly (small percentage) has it in their vehicles. And if they have 6 vehicles, then are they going to subscribe in all 6 of their vehicles? If it wasn't for a certain must have radio station that I like to listen to, I wouldn't even have XM/Sirius radio anymore. The reason is that they charge me for each and every radio I own but I can't take my car radio with me, nor do I like the octopus like wiring scheme to take a home XM radio to put into a car.
HD radio, on the other hand, is "broadcast" radio, meaning that no subscription is required, anyone and everyone with an HD equipped radio can hear, and because HD radio can also listen to ALL non-HD content, the radios would never be obsoleted even if no HD radio towers existed in your area. Also, because the broadcast radio band is completely govered by the FCC, there may come a time when there is not enough bandwidth is available to cover demand. On FM, there must be a 200kHz span between stations and with 20mHz of available FM band radio bandwidth, there is the potential for 100 stations to coexist if every possible spot is filled. On AM, there is only 1.07mHz of bandwidth (1070khz). Potentially, there exists 107 slots in 10khz increments but anyone that has listened to AM knows that it is far more "wide-band" than FM which is more selective but you would expect that being a much higher frequency and far greater space between stations (200khz as opposed to only 10khz). Also, because AM radio by it's very nature (lower frequency) can travel far greater distances than FM, the granting of stations is much more stingy in an effort to avoid cross station interference. For this reason, I do believe that HD radio benefits AM far more th an FM. Now as far as the benefits go, HD radio allows AM to be broadcast in Stereo and also allows multiple stations on the same station. Confusing? Much like today's digital TV broadcast stations, you can tune to, for example, 680kHz and there might be 680-1, 680-2, 680-3 stations being simultaneously broadcast using the same frequency where only 1 station originally hogged up the entire bandwidth. To me, because this technology exists, I believe it's only a matter of time before the FCC would mandate greater bandwidth usage efficiency. Maybe not today, or maybe not this decade. But from what I've seen in how our country and technology has grown in the past 3 decades, it won't be long and while it might not be exactly the "HD-radio" we see today, there is bound to be some similar form of greater efficiency broadcast technology.
