A little over 3 years ago forum rules were posted and included was:
You have every right to disagree with your fellow community members and explain your perspective.
Do not post “offensive” posts... Any material which constitutes defamation, harassment, or abuse is strictly prohibited. Material that is ... obscene, racist, or otherwise overly discriminatory is not permitted on these forums. ... Use common sense while posting. Remain respectful of other members at all times. All posts should be professional and courteous.
However, you are not free to attack, degrade, insult, or otherwise belittle them or the quality of this community.