I don't understand why Lauren would be the go-to doctor for all things Fae. Surely, there's got to be tons of other Fae doctors out there who probably have CENTURIES of experience and knowledge over her. It makes no sense. Tamsin pretty much shot this down when she so casually mentioned "Tickbalang" in 3x10 while Lauren was flipping through her books. Bo: "I'm alright, but I'm not perfect." Tamsin: "Yes, you are. To me, you are."
Tamsin has always been able to name a fae species at the drop of a hat. Imagine what would have happened to that poor squonk if someone else had gone with Bo to Brazenwood. "My personality is who I am... my attitude depends on who you are..."
You can blame the writers, but let's not forget that everything they right and publish become canon. No matter whose fault it is for writing a poorly constructed back story, the poorly constructed back story is still strongly present and a factor in the overall character. "Why do you care so much!?"