Are you referring to countries with languages which are relatively difficult to learn for many foreigners? Or countries which aren't particularly friendly to foreign tourists? Or what?
Viewed in this way, one can understand why not being fluent in a language is often met with rudeness.
People will find all sorts of reasons to create in and out groups, but I can’t imagine a country setting a policy of limiting learning of their official language. To protect their culture they’d want it learned so it doesn’t get supplanted by another external language.
Languages evolve and are in constant flux as words come and go and their meanings change.
It’s the same reason that we haven’t all evolved to a single universal organism.