Banning entire countries helps a lot. I don't want to name certain countries, but let's assume it's one where it's common to see human corpses floating on a big river.
That doesn't help narrow it down. I live in Seattle and the first think I thought of was a popular tiktok of teens finding a corpse in the river last month.
Apart from the fact that banning an entire country from contributing to their code would be antithetical to the Wikimedia foundation, if you're implying the country which I think you're implying (which is also where I live, btw) you'll:
1. Ban a burgeoning tech industry which has produced over 20 unicorns,receives billions in funding from across the world and produces world-class tech talent;
2. Ban millions of other OSS developers from contributing; and
3. Just lead to SEO spammers picking out other impoverished countries to spam from, which means finally you'll end up with only people from the "west" being able to contribute in any way.