Intellectual rigour is important. I place a high value on it, & wish that other people did as well.
But if you say to someone, "because you belong to X group or have Y characteristic, I should be allowed to deny you access to housing, medical care, & employment, or even to kill you, without suffering consequences ― prove me wrong", you should not expect a reasoned argument. You should expect a gunshot to the chest, followed by one to the head.
At the risk of being ignored by ―continued
Exactly this kind of rhetoric is still with us.
Furthermore, the Internet (mirroring society in general) is full of people who adopt an entirely degenerate form of "debate", in which arriving at an answer is not important, much less its correctness. They constantly switch premises, even contradict themselves.
This can be a healthy intellectual amusement, but often is used (and this, I think, is what the poster alludes to) as a means of harrassing people.
"I appreciate SDF but it's a general-purpose server and the name doesn't make it obvious that it's about art." - Eugen Rochko