That will be the argument used against you....that you can't count on or rely upon it again in 2022.
But there you have at least three organizations in Houston, New York and Boston who aren't afraid to put their money where their mouth is...there's no way you can argue that any of those guys are significantly less risky (and some, moreso) than Carlos Rodon.
And part of it's also the the psychological side of things, the message it sends to your fan base...that we don't believe in our own homegrown player more than say, Craig Kimbrel, who was an absolute train-wreck with the White Sox and had very little if nothing to do with their 2021 playoff appearance.
If there are DEFINITELY teams out there willing to spend that $18.4 million (and the Dodgers would be another, Giants letting DeSclafini and Alex Wood go have money to spend, along with Posey retirement)...there's not at least 6-8 teams out there that would be interested in Rodon?
As it stands now, the only 50% convincing argument I've seen for Kimbrel is matching up with the Phillies, but there aren't many more teams, and the Phillies got by well enough at the back end going cheap/er, they just need to improve their 6th-8th inning guys and can spend a lot less than $16 million to accomplish that.