I think we are pulling at hairs, differentiating between the two; especially for the point of 22 questions, where the referenced material provides a clear and contextual link between the two terms. I more commonly hear the two terms used in replacement for each other, and to be perfectly honest, I was not aware that there was a distinct difference; and there does not seem to be a big one. At least, not big enough to warrant entirely different tags.
Let's take a closer look at the referenced definitions:
"Internationalization (i18n) the process of changing your software so that it isn't hardwired to one language/locale/culture.
Localization (l10n) the process of adding the appropriate resources to your software so that a particular language/locale is supported. It's bigger in scope than just this Wikipedia entry, but it's a good start.
These definitions only provide one clear difference: internationalisation refers to adapting software to be compatible with other languages; localisation refers to adapting software to be compatible with other languages and cultures.
Let's take a look at the next two highest-rated answers (emphasis mine):
The second highest reads
"According to Apple:
Internationalization is the process of designing and building an application to facilitate localization. Localization, in turn, is the cultural and linguistic adaptation of an internationalized application to two or more culturally-distinct markets."
The next highest reads
"Internationalization prepares your application for localization. For example, you might encode characters stored in your database in Unicode (utf8mb4 instead of latin1), moving strings to resource files, enabling the use of date, time and currency formats, etc.
When you wish to sell, for example, a Chinese version of your app, you'd then localize it by hiring a translator to build the zh-CN resource files, and use a new date/time/currency format."
In fact, using one term to describe the other is a common pattern across a lot of the answers supplied to the referenced question.
It is clear, at the very least, that these two terms are heavily entwined. It is difficult to find a clear definition of one that does not involve using the other.
Furthermore, through the described differences, I fail to see how one might be knowledgeable in one without the other. Especially when the clearest definition of "internationalisation" I can find effectively reads "making ones program more adept to localisation".
At best, they should be synonyms; but given the fact that only one of these tags actually has usage, I have to question whether we really need to create the other simply as a synonym. They say you shouldn't fix something that is not already broken; this feels like we are trying to fix something that doesn't exist, yet.
internationalisationtag? :P \$\endgroup\$