Since the short attention span youths have already abandoned radio, seems to me it's best to market to those still listening. Those people grew up on radio from the 50's to the 80's which was personality driven. Jocks are expensive, especially live and local ones but back in the day, especially in mid to larger markets where there were two or more CHR's that were battling each other, personality made the difference. So why fix what wasn't broken?
As for the content from the personalities, again, it was local. Talking about local events and advertisers. Telling relatable stories about the song or artist that was just played (or about to air). None of this rip and read garbage about the latest tik tok trend they read about on yahoo news. Phoners are absolutely engaging! To hear the excitement of someone being aired for winning a contest or for offering a quirky or silly opinion for a "question of the day" brings the listener in closer to the jock and by extension, the music and advertisers. Teasers are still a great wat to encourage listeners to hang around. If you're a big Swiftie, won't you linger if you know her newest hit that you adore is coming up in ten minutes?