This is false. Here in America, the dumber half of the population thinks/writes/says "would of." The frequency of this error will vary by country, but there is no country where every citizen thinks/writes/speaks in a well-educated manner all the time.
Born and raised in the States. People who think they're hearing "would have" are hearing (and eventually repeating) would've. As a retired teacher who career changed from 15 years working in publishing and curriculum design, I'm quite familiar with how people are sloppy when translating the speaking voice to the page (to vs too vs two, their vs there vs they're are a couple examples that get routinely abused in this game as well . . . are those errors okay with you as well?)
Should the writer be writing "Djeet Jet?" for "did you eat yet?" I'd argue that if you were having a conversation with somebody, that you wouldn't know with metaphysical certitude whether (not weather, that's another one) the person is saying would've versus would of. So, what is particularly wrong with getting it correct for the reader? The argument that it's a stylistic and strategic choice by the writer is a dog that won't hunt given the general sloppiness of the writing in general.
For example, some of the characters in the course of a single conversation use "would have" in some sentences and "would of" in others. Is the person "uneducated" or not? And if all the characters are similarly flawed, are we to conclude that every single character is uneducated in the exact same way, or is it more likely that the author continues to ignore some basic grammar and usage issues that have been pointed out with each release? There's a difference between being intentional in one's writing and being sloppy . . . you can put a pig in a prom gown, but it doesn't make it the homecoming queen.
And as an American, I will definitely concur with the observation that there's a gigantic population of folks in this country who are smart like a sack of hammers. If the rest of the world didn't know that already, they sure figured it out over the last six months or so.