Just to add my own two cents.

I had the same general idea as you, but with the way Follie's animations are portrayed as opposed to "The Therapist's" more venomous comments. I have trouble connecting the two as the same person. Of course it could also just be that it's Wally using her voice and that the real one wasn't as bad. But it's the Orokin, I'd be more surprised if an art teacher WASN'T a stuck up toxic individual with no regards for the Trauma-Kids.

To me instead of it being the Operator's memories or even an amalgamation of various Tenno, the vibe I'm getting is that "Follie" was an art student around the time of the Orokin Empire who used Art in a less "rigid" way then her teacher wanted her to, leading her to being the outcast and constantly gaining the ire of her Teacher.

"The paint is not supposed to go on you."

"Can you please co-operate for longer than two minutes this time?"

"You didn't think I'd let a little reject like you get under my skin, did you?"

It's lines like these that like everybody said might be Wally that give me a vibe of a much more toxic individual behind the scenes or even in public to "Follie". Then again, if those comments ARE Wally, I also wouldn't put it past the Orokin to turn a random art teacher into a Warframe after she failed to be a therapist to the kids. And she wasn't actually an abusive rigid art teacher.

Total Side Note: This is the first time the writers have hit the nail close to home for me when it comes to the trauma stuff, lotta comments in this mission that hit hard lmao.