Major trigger warnings up the wazoo I had "speech therapy" and "occupational therapy" when I was younger which was really ABA in disguise. Here are the things I went through.
I was told to play with Play-dough, which I thought was stupid because I'm not 2. Later I was told to tie a string around my arm. When I was unable to do this, they grabbed my arm as hard as possible and forced me to wrap it over and over again, while never letting go of my arm until I managed to wrap it around my arm. If I did any sort of "fidgeting" I was told to sit in the chair, and was watched to make sure I didn't "fidget". If I did "fidget" then they would yell.
If I "fidgeted" in any shape or form they would take my backpack away from me and wouldn't give it back until I stopped "fidgeting". They would also hold hands down until I stopped "fidgeting". I was also not allowed to go to the bathroom until I stopped "fidgeting".
If I said things in a monotone voice, they would force me to keep saying certain sentences until I got it. I wasn't allowed to take breaks until I didn't speak in a monotone voice.
If I had gone nonverbal, my backpack was taken away from me and wasn't given back to me until I spoke, and I spoke in a voice that wasn't monotone.
If I tried to leave the room so I could calm down from sensory overload, they immediately blocked the door, and trapped me inside until I did what they wanted.
TLDR; ABA "Therapy" is Gay Conversion Therapy for Autism and tortures Autistic people.