Unfortunately, that's what it has come to. Everyone has to have a role and you can't deviate from that role. Kimbrel is a perfect example. In actual save situations, he's been really good (high wire act, but he's gotten the job done 90% of the time). In non-save situations (tied game or behind) he's been awful. He's hardly the only one in the majors.
And back in the day, Kimbrel would have pitched both the 8th and the 9th.
Dojii has it right, though, when it comes to managing these guys, no thanks.