Is the argument that we can't use over to mean more than finally over and done with?

There are some so-called "rules" in the English language that confuse everyone from native speakers to English language learners. Sometimes there isn't even any grammatical basis for the rules—some "expert" long ago decided it didn't sound like proper English, and it stuck. Don't use "over" in place of "more than" is just such a rule. When even grammarians are arguing over a language rule, what are English language learners and teachers supposed to do?

The Argument

In 1877 William Cullen Bryant, the editor of the New York Evening Post, decided that over should never be used in place of more than (and supposedly he never gave a reason for this). Just to put it in context, he also forbade the word pants in place of pantaloons. But for some reason, this over ban stuck. So over with a countable numeral (e.g., Over 100 people signed up) was considered incorrect; more than was the only acceptable choice, according to many grammarians of the day (e.g., More than 100 people signed up). Of course, you could always use over as a preposition of place (e.g., The dog jumped over the fence), but the adverbial sense of over was a big no-no in many circles, especially among journalists. (For more on over as a preposition, see Commonly Confused Prepositions: Above, Over, Below & Under.) On the other hand, many have argued that there is no basis for this rule and have demonstrated that over (meaning more than) has been in use since the 14th century.

The Good News

Most of the major style guides now list over as an acceptable alternative to more than. The Chicago Manual of Style, for instance, has had this entry since 2010: "over. As an equivalent of more than, this word is perfectly good idiomatic English." (5.220) AP Style came around in 2014. Since then they have said that over and more than can be used interchangeably to indicate greater numerical value. Though there are still dissenters out there, it seems as if, finally, the backlash over keeping this pedantic rule is more prevalent than the backlash over getting rid of it.

Conclusion

Feel free to use over instead of more than whenever you wish. As Merriam-Webster's Dictionary of English Usage states, "There is no reason why you need to avoid this usage." The major style guides also point out that you can use under instead of less than/fewer than. But what should we teach our students? I tell my students that both over and more than are acceptable to use. I do warn them that they might have teachers or bosses in the future who feel strongly one way or the other, and remind them that more than is the "safe" choice. But I also tell them they will see and hear both over and more than, so they shouldn't be afraid to use either one. I think this makes a great discussion topic as well. I mention the controversy and ask my students if they have such controversies in their own languages. What do you think? Over to you.