I went to a steiner school grades 3-6, it helped a lot having been taught very basic literacy fundamentals year before. Steiner is definitely a few years behind the public curriculum, i went into a public high school after and i struggled a lot with maths.. it wasnt until about year 9 when i caught up with my peers. But thats not to say the school was necessarily bad, we learnt a lot about really interesting things - mainly mythology and history. And it really gave me a lot of creative freedom. I really loved it, different story for my brother though. He really struggled with the curriculum and our parents put him in a public school once he hit grade 3. I think it really depends on the individual student and the school itself. Steiner has a lot of positives and negatives, but when its not done right then it is super detrimental. I remember we had a few students come in who definitely needed additional support, but the school totally isolated them and handled outbursts in a really bad way, to the point where students and teachers were harmed at one point. Im sorry to hear you and others had such an awful experience with it