The point still stands, in the minutiae you're addressing. People post absolute garbage opinions on a regular basis, and are free to do so, as long as their platform allows it. This doesn't go into the consequences of pissing off a lot of people, but you're still free to do it.
The point does not stand. I don't think any set of rules that sees "N***** N***** N*****" as acceptable speech should be respected, nor any person who thinks that way.
Note, Mr Fry is a gay man and has championed gay rights. His very existence is offensive to backwards conservatives. This quote often gets shared without any context.