I agree. In general I identify as very progressive (especially by US standards), but I hold some opinions that are somewhat outside of the leftist norm, and I'm more or less completely unwilling to discuss them online as I don't trust that I will be treated in good faith.

The sad thing here is that I'm genuinely open to having my opinions changed, and have a history of changing my view in response to argument in the past. But can't have my view changed if I'm too scared to even have the discussion ;-).