The Pageviews tool provides valuable information about the most popular articles in every project.
However, it would also be useful to have information about the most popular articles by country. Countries and languages are very different. This is especially important for languages that are spoken in many countries, such as English, French, and Spanish: the most popular articles in U.K., U.S., Australia, Nigeria, South Africa, and India are probably quite different.
In such a tool it would be useful to see the most popular pages in all the projects; in such a case, the 100 most popular pages in Moldova will probably include articles in Romanian, Russian, and English Wikipedias, and possibly also some Commons, Wiktionary, and Wikisource pages. It would also be useful to filter for both country and language and, for example, see only the most popular English Wikipedia articles in Moldova.
It probably makes the most sense to integrate this into the existing Pageviews tool, and add a new tab to the current Langviews, Topviews, Siteviews, etc. However, it may also make sense to set it up elsewhere, for example in Turnilo, Superset, or some other platform.
I once raised this at the Analytics mailing list: https://lists.wikimedia.org/pipermail/analytics/2018-July/006385.html . The query suggested in that thread by @fdans works, but it's slowish, and there's no fast API for this, as there is for pageviews per project.
There are probably some blocking privacy issues. They should not be a total blocker, however. It's OK to filter out some problematic entries in small countries or languages where personally identifiable information can show up, but it's probably fine to show the top 500 viewed pages in Nigeria (just as an example).
Beyond the general "zeitgeist" curiosity, such a tool will be particularly strategically useful to people who want to develop projects in languages that are spoken by many people, but don't yet have a lot of articles. This is true for many languages of India, for example, where English is the most popular language by far, even though most people there speak other languages.