From my lived experiences, I think that TF "victims" would eventually forget what it feels like to be human. They may still desire to go back, but I think the longer they spend in their new forms, the less they'll know what it entails to go back.
I mostly say that because of all the changes I've gone through. Whether they voluntary or not, good or bad, I don't really remember what my life was like before they happened. I don't remember what my body felt like before I transitioned. Nor do I remember what it was like before I got disabled (excluding the disability I've had basically since birth, of course).
They're just things I live with. Do I wish some of these things would go away? Of course! But I do not know what that would actually feel like even if I have experienced it before.
Basically I just love some loss of humanity in transformation x3
So you're thinking to yourself, "Hey, you know memory recall is an active process" and then you're considering Neuroplasticity in the human brain, and you might think this kind of sensory-linked memory is immutable. Turns out, naw it isn't and the various hypotheses about why are pretty cool. Memory of all types is pretty fragile and prone to not only errors but also revisions during recall, one of the famous studies about adults who witnessed 9/11 is that the resolution of the memory got denser the further away the memory got (meaning more details "recalled") Hirst, et. al., 2010. This speaks to an interesting phenomena about human memory where the brain actively encodes and decodes memories during the recall process, I like to imagine our modeling of memory as unspecific: "We have the Zipcode, but not the Address". Memory Manipulation in humans is extremely variable with some having exceptional recall, resistance to re-encoding errors, or "super memory"Hyperthymesia, via Wikipedia. Out the other end of many of our studies about memory is that it's pretty fragile and the importance of documenting independent of our lived experiences is actually really quite high, and if you're unlucky enough to have ADHD like me you make errors in recall constantly.
The idea of what makes "you" stand out as "you" in particular is an interesting question physiologically speaking, so provided you're not going all-in on a more mythological / spiritual metaphysic, you can model out some quirks to make your Transformation fiction look interesting. It doesn't even have to be all that smart either, the brain's kinda squishy and molds in unexpected ways if you look at our case history!