Not true, there's not evidence of that

None of the trans people prosecuted and sent to camps, and arrested were ever offered that as an option. Trans people were seen as inherently sick, so even if they detransitioned, they were seen as poisoning society. There was a book at the time that was put out The problem with the tranvestite that explained trans people were inherently sick and couldn't be cured.

There were a few rare cases were certain people were allowed to live if they detransitioned, which naturally lead to suicide. However there's other cases of people living as their assigned birth, and when they secretly did things as their chosen gender and were caught, they were sent to death. Please know detranstion is really not a viable option for most trans people. Some people chose to detransition for various reason, but most don't and find it appalling.

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