It might sound "completely over the top" or "too absurd" but it's actually pretty close to what happened in real life. Blanchett's team even consulted the real woman who inspired Sofie and I assume the slight changes to her story might have been a result of that. She really did join a cult, took on a new identity to escape the cult, and wound up in detention for 10 months before she was found following some media interest.
I went in with an idea on what to expect because I started reading about it when news about Stateless came out in 2015. Back then it was announced as just her story. I found The Monthly's article to be the most informative but it needs a subscription. Sites like Popsugar, Mamamia and even Oprah also have articles on her story, however. I got even more interested when I read about the new storylines added.
It has some slow moments and I wanted to know more about Rosna and the Asian lady but I actually really enjoyed Stateless. I found Sofie's and Ameer's stories to be the most compelling: Ameer's because his story, especially his scenes with Mina, is very moving; and Sofie's because of how big of an anomaly that real case was to have led to reforms (that unfortunately proved short-term), and partly because of Strahovski. While I don't think Sofie's story overshadowed the others, Strahovski's performance was head and shoulders above her cast mates.
I think Stateless is something everyone should see. That said, I don't think I have the mental or emotional fortitude to watch this show again in the very near future.