However, as a practical matter, correcting someone on their incorrect usage is off-putting, a clear dick move. They are not going to learn from your noble example. Save your time, and your reputation, and move on. I recall seeing some fluff Sunday morning show piece about a couple of guys who would go around to restaurants and "help" them correct their menus, usually over misspelled words or misused apostrophes. Life is just too short.
The "literally" thing actually makes a small bit of sense to me, because there's not really a common-usage adverb -- aside from "figuratively" itself, which might be somewhat unwieldy in a casual conversation -- that conveys the figurative nature of the exaggeration in question. We know that the speaker's head did not literally explode, and yet it's scarcely worth the trouble to point out that that word does not mean what they think it means. They know, that just happens to be the handiest word at their disposal.
Now, I'll admit that I take a breath when I see the aforementioned misspellings, and especially the misused apostrophes, because the rules on those are so simple -- possessives, not plurals. Writing "ect." (or saying "ek cetera") is another peeve, because "et cetera" has a literal meaning, an actual function. "Should of" instead of "should have", that sort of thing. Approached as tools with functions, these things are not at all complicated.
But habits -- especially bad ones -- form through inattention and lack of caring. This is what the corrective pedants, well-meaning as they are in their quest to preserve the care and feeding of our noble, evolving language, may not quite get. People use "ect." and can't get the correct "your" or "there" homophone because they don't give a shit. By definition, correcting someone who clearly couldn't care less will not correct the mistake, but merely annoy that person.
Back in the chat forum days, I had several lively discussions about this subject with professional academic linguists, people charged with the mission of identifying, classifying, and organizing the various phonemic and grammatical constructs of languages. As a kid, I was fascinated by a variety of languages, and gained at least minimal competency in most of the major European languages.
The more you learn about language -- especially one as widespread and multiply sourced as English -- the more you realize that it is never static, it's a river that flows slowly but flows nonetheless. As with political systems, the outcomes of languages are frequently a result of a large enough mass of users who don't know or care to understand the nuances of what they're engaging in. They deploy it to convey their own immediate use, and some of it will accrue habitually. The more they read and/or write, the more competent they will be in hewing to convention, as one might imagine.
And that, ironically, is where preservationist linguists fall short, imho. It's easy to understand the impulse to chronicle and archive one of the thousands of dying languages around the world, spoken only by a dwindling group of elders in a remote village. But that impulse contradicts what we've noted above, that languages evolve with use. A dying language, by definition, is no longer one that is being used. It is intellectual lepidoptery to stipulate that a language that is dying out precisely because of its lack of use and interconnectivity has any utility, beyond capturing the oral history of the remaining few who speak that language.
In the end, the pedantic attention to upholding the simpler and more obvious conventions of language comes down to cash in many instances. I've been on plenty of hiring panels, and thus reviewed hundreds of résumés over the years. And I can tell you right now, when I encounter a misspelled word or a misused apostrophe on a cover letter or résumé, I don't bother correcting jack shit. I don't have the time. It just goes straight into the round file, I won't even bother to finish reading it.
And I'm far from the only one; I have heard and read plenty of hiring managers say the exact same thing. Ultimately what it comes down to is whether or not someone can be bothered to pay attention to what they're (as opposed to their) doing, and if they can't, hiring managers won't waste their time with that stuff.