Yeah - to be honest, what they did to Saru was quite mind-boggling! Like, I loved the episode itself. But it has been a tremendous dis-service for the character since then.
I actually really liked "prey"-Saru. That was a completely new, and neat concept. And it was actually great to see someone overcoming his fear and instincts, and work as a completely functional being and officer regardless. It was - by all means and purposes - what made him special.
Taking that away from him, was IMO akin to taking away Spock's logic. Or Worf's honour-fetish. Like, yeah, some things were handled a bit clunky (like the "fear boner"). But so were Spock and Worf early on. I just wish they'd have actually sticked to the concept, and got better at it! Instead - Saru now has nothing that makes him special anymore. The only thing saving him is the fantastic acting. But apart from that, he acts like any other Officer would. Esentially, he lost his unique perspective on the world. That was such a shame.