This is exactly what happened in Dallas with Audacy's KVIL. Alt 103.7 (launched the same day as Alt 92.3) was circling the drain. They added lots of 90s gold, then gradually added active rock crossovers. It stole the audience from IHeart's Active Rock station, which flipped to Sports/Talk last Monday. I'm surprised they didn't try a similar approach up there.
I remember reading something a year or two ago about how Alt 92.3 refused to use the word "rock" in any of their marketing, which supports others' posts on this thread that the Alternative Rock format is so segmented nowadays. It's really a hodgepodge of maybe 5 different formats (active rock, AAA, 90's alternative, pop, and indie). At one point, I think they saw themselves as a Modern/CHR station, and the bench is pretty shallow in that subgenre after you play the latest Imagine Dragons, Machine Gun Kelly, and Bishop Briggs hits that crossover to pop. Then they oscillated between the other alternative subgenres in the past year or two, especially 90's gold.
Either a more active rock lean, or a potentially older skewing "softer" AAA lean probably would have helped.
They couldn't pick a lane.