What's the most petty/pointless/pedantic hill you're willing to die on?
For me, it may be that the toilet paper roll needs to have the open end away from the wall. I don't want to reach under the roll to take a piece! That's ludicrous!
That or my recent addiction to correcting people when they use "less" when they should use "fewer"
A while ago I had people arguing with me that the word "is" means basically the same thing as the word "was" and that I was being pedantic by saying it didn't.
Witan þæt, in sooth, þæt wisdom of ealde tunges is of great worth, forsooth. Þæt tongue, fram eallra yore, hath been a vessel for þe heah wisdom of our forebears, and to hold fast to þe staþolfæstness of grammar and wordcraft is to keep þe richnesse of þe auncient lores alive. By þe seofonfold strength of prescriptive ways, we becomen keepers of þe pure tongue, untainted by þe waning of times and þe unstedfast weathers of speech, þereby granting us þe true understanding of ealdan wisdom and þe right ways of our folk.
It's a noble fight, but a losing one. Language changes so fast and since common people make common usage, we're bound to shift over time to something truly incomprehensible like actual Old English is to what we speak today.
You can keep your prescriptive linguistic nazism. I'll enjoy my descriptive freedom.
In all seriousness, prescriptive linguistics have a limit in a sense that language is formed by usage and that's inherently a "descriptive" process.
It is possible to prescribe language when you're in a majority of users, but after some critical mass of people there is nothing you can do. Even when they're technically wrong.
A fact is an observation made in nature. At 8:40 PM PDT I read from my kitchen thermometer 73°F. One datum.
So often people use the term fact to suggest something is true, e.g. Gravity is a scientific fact. It's an easily demonstqble phenomenon. There's a mathematical law that predicts the interval of falling bodies. You can make and present facts that demonstrate the consistency of gravity, but it isn't a single fact in itself.