The reaction isn't triggered by ignorance.
Please show your evidence. The Washington DC brouhaha over the use of "niggardly" was quite clearly triggered by the complainers' ignorance of the meaning of the word. They didn't think "niggardly"
sounded like a racial epithet; they thought it
was a racial epithet.
Word-origin and dictionary word definitions are not the only things which determine how a word will be perceived when being nonchalantly used by certain people in the presence of other certain people.
That's just a fancy way of saying "Ignorant people don't know what words mean."
As for dictating, it seems that the ones doing the dictating in reference on how the word HAS TO BE reacted by African Americans when used by whites in their presence are the people hell-bent on routinely deploying it.
"Routinely deploying it"? Who do you know who "routinely deploys it"? Who have you ever
heard of who "routinely deploys it"? Perhaps if it
were "routinely deployed," more people might understand what it means and wouldn't make asses of themselves objecting to its use.
The same holds true for "black hole."
As you already know, the word includes a term made notorious via Caucasian usage against enslaved blacks.
You should look up the etymology of "niggardly." It has absolutely no racial connotations.
English is a very rich language, in large part because it incorporates words from many different languages. "Niggardly" is from middle English; the "n" word is a corruption of "negro," which has Latin roots. And "niggardly" has a distinct meaning from other synonyms expressing similar ideas - that's why we have different words. This is from dictionary.com's definition (bolding mine):
Usage: Avaricious, Covetous, Parsimonious, Penurious, Miserly, Niggardly. The avaricious eagerly grasp after it at the expense of others, though not of necessity with a design to save, since a man may be covetous and yet a spendthrift. The penurious, parsimonious, and miserly save money by disgraceful self-denial, and the niggardly by meanness in their dealing with others. We speak of persons as covetous in getting, avaricious in retaining, parsimonious in expending, penurious or miserly in modes of living, niggardly in dispensing.
By demanding people stop using "niggardly," you are displaying the same mindset as O'Brien in George Orwell's
1984, wherein he boasts that the Party is deliberately shrinking the English language as a means of limiting people's ability to think. If you have the word "good," then you don't need the word "bad," or any of its variants, because "ungood" is a perfect substitute for "bad." And you can easily intensify "good": "plusgood," "doubleplusgood," and likewise, "plusungood" and "doubleplusungood."
Orwell posited the fictional shrinkage of language as a means of thought control. You are apparently advocating it as a means of avoiding offense to the ignorant. Perhaps you believe we should avoid any possibility of offending anyone with limited language abilities by adopting Orwell's
1984-style constructions. One root word will suffice - "Generous":
Ungenerous = cheap
Plusungenerous = cheaper
Doubleplusungenerous = cheapest
Frankly, I think "doubleplusungenerous" is a much uglier word than "niggardly."
This is from a list of rules for good writing I once came across:
In addition to these large rules, there are some little ones. These require that the author shall:
12. Say what he is proposing to say, not merely come near it.
13. Use the right word, not its second cousin.
The complete list can be found
here. It's by Mark Twain, who knew a little bit about good writing.
