Ironically it's happening just as many of those hosts are about to exit the target demo. So what some of these stations are doing is bringing in a new generation of hosts. One of the best known is Bobby Bones. He's a millennial country radio personality who iHeart has syndicated on about 50 or so of its country stations. They have also apparently made an arrangement with ABC to have him on a number of their reality shows. He won Dancing With The Stars last year. So that appears to be a likely template for the future. Of course that change immediately alienated the boomers, who are sticking with the heritage hosts as long as they hang around.
Keep in mind that while this generation grew up with computers and phones, they also grew up listening to your car radio. So they know the radio, although they associate it mainly with you. That can be either good or bad, depending on how they view you. They listen to their Spotify list, which is usually a smaller playlist that a typical radio station. It may last for an hour. They listen to that because most of the radio stations are aimed at people older than them. A day will come when more of the people on FM will be from their generation, and will play more of their favorite music. It will come at a time when they will have less time to create personal playlists, so hearing someone else's list will save time. The main attraction, though, still will be those on air people.