~ Food Has Power ~
Fermenting does not decrease the "goitrogenic effects" of cruciferous vegetables, cooking does. However, the issue is that most people consume inadequate iodine-containing foods (not supplements, imo).
"Over the past 50 years, however, researchers have determined that there are no such "negative" substances in food, but only health-supportive nutrients that are not a good match for certain individuals because of their unique health history and health status. Five decades of research have also determined that certain nutrients - like tyrosine, iodine, and selenium - play a unique role in thyroid health."
I'd worry more about ADDing iodine-rich foods (sea veggies), selenium-rich Brazil nuts for essential nutrients. And avoiding caffeine which is a thyroid suppressant.
Fermented cruciferous veggies are eaten by the forkful with MANY health benefits. I don't worry about it. And steamed veggies are an easy addition to raw veggies which provide important enzymes.