To start, I'm basing my impressions on the Netflix show alone. I've never seen the Winx Club series. I actually didn't even realize it had such a long-standing history beyond some short-lived toy line.
As someone who enjoys dark fantasy and magical-themed shows like Sabrina, The Magicians, and even The Order, I decided to give Fate: The Winx Saga a look. I didn't expect much from it, but what I saw was almost physically painful. It's a pretty standard by-the-numbers teen drama show. You have the standard-issue misfit protagonist who honestly seems like she needs to be sharing a room in a mental facility with Hellboy's Liz Sherman (the latter actually being an understandable and likable character). There's the blonde mean girl from the old-money background. The blonde hot boy who is torn between the mean girl and protagonist. The teachers that range between authoritarian and bumbling stereotypes. There is the dark bad boy. And perhaps the most painful of all is Terra, who is the standard-issue "large girl with body issues that contribute to her social awkwardness."
Upon seeing the preview, I had hoped that their inclusion of someone who wasn't just the typical skinny girl would mean there would be some fresh elements. Alas, she is used as just another character whose weight puts her outside the norm in this world and is therefore hyper aware of it socially awkward as a result. It's the kind of inclusion that is almost more damaging than its omission because it just perpetuates the sad, tired stereotypes.
Even for a teen drama popcorn muncher, this is just such a cookie-cutter piece of fluff that it's worth passing over. I went into this series with pretty low expectations, and even those were let down.