Not the thought itself but I will always defend people's right to express them.

First of all, because John Stuart Mill's argument* makes rational sense.

But also for another, more modern reason: to help us understand the contextuality of complexity. How and why has someone developed this opinion and how does that help them in their life? Let's park the heuristics of morality here for an instant in favour of gaining a deeper understanding.

Ecologist Ian McHarg talks about creative fitting. An organism adapts to its surroundings but also adapts its surroundings to it, in the aim of creating a better fitting. A better quality of life. Brain computing power is very costly, so for some idea to be put in and stored it must be worth the effort. But its price also means change doesn't come cheap and will be resisted. So for some reason in history, this idea was useful for survival. Locked into the collective culture and passed on. If you dig deep into how and why this idea set foot in Aunt Paty's it will teach us a lot about contextuality and complexity. Lessons we then can go and apply to our current day situations to get a better grip on our own current programmed biases. The fact that Mary doesn't hold these same ideas means that her conditions are different and her brain software has been programmed differently to assure her a "better quality of life". (there is an analogy with how AI is programmed).

So instead of censoring, we should be teaching from a young age onwards kids insight into how to read and navigate complexity. (a vital 21st-century skill) If society were to start teaching 7-8-year-olds this today, racism in society would be irradicated by the time their generation reaches its end. Society will have rid itself of this piece of software as it's a waste of space as it (no longer) serves any purpose. It's history.

So you see, there is one he** of a storey hidden in there. Just keep digging, and keep the door always open.

“John Stuart Mill argues that free discourse is a necessary condition for intellectual and social progress. We can never be sure, he contends, that a silenced opinion does not contain some element of the truth. He also argues that allowing people to air false opinions is productive for two reasons. First, individuals are more likely to abandon erroneous beliefs if they are engaged in an open exchange of ideas. Second, by forcing other individuals to re-examine and re-affirm their beliefs in the process of debate, these beliefs are kept from declining into mere dogma.”

https://en.wikipedia.org/wiki/John_Stuart_Mill