I don't know his motive, no will I pretend to. But I am a huge fan of the late Jim Bouton and Ball Four. Truth is truth, no matter the motive, anyway. I will not villianize the whistleblower. He could have been the guy (as a pitcher, he didn't benefit at all) that was forced by peer pressure to assimilate into the team, and just stay silent. But after all the lies, and he didn't need to be part of the team, he spoke up. Good for him. Good for the good cop that doesn't buy into the crooked code blue. And I am one that doesn't care at all about sign stealing, and thinks it is up to the defense to figure out how to keep the signs secret, regardless of how they are stolen.
Sure, I agree that truth is unwavering no matter how you arrive at it, but that isn't what's being questioned. If we're assessing character, then Fier's motives certainly should be scrutinized. Did his moral fiber suddenly grow so strong over 2+ years that he felt compelled to blow the whistle, or was he a jilted ex that watched his former team and current rival, which kept him off the playoff roster in 17', win the AL West ahead of Oakland and make deep playoff runs, while the A's failed to make it out of the WC game? Fiers isn't the "good guy," more than any other player on that 17' roster, and he certainly benefitted from having an offense that knew what was coming.