Sometimes the truth is unpopular and seen to be uncivil when bluntly stated. Should we all rub blue mud into our belly-buttons and sing praise of everyone's opinions?
Truly healthy discussion inherently involves people expressing ideas and opinions that may be provocative. Some people very likely will be offended by these ideas. Some people will get angry. Some people won't believe what they're reading or hearing. But those are all good things. They indicate that there is a wide variety of thought going on.
Communities that are kept "civil" through the use of excessive moderation, for example, thrive only in a very superficial way. Given enough time, intellectual inbreeding happens, where the vast majority of participants adhere to a very strict dogma. Any real contemplation is quickly extinguished. The end result is a very bland type of thought, devoid of real substance. It's not truly healthy, even though it might look good on the surface.
Or maybe for some opinions you can't, if so I'd like to hear an example (intellectual curiosity, not snarkiness).