I was being a bit cheeky with a T. S. Elliot/Andrew Lloyd Webber reference. Sorry it went over everyone’s head.
Yes, I avoided a road/border example because of the potential for confusion. It’s true that many examples can be handled by name:left and name:right (or, for routers, name:forward and name:backward). That leaves the question of what to put in name. If you omit name, someone will inevitably fill it in, incompletely. If you add both names to name, the delimiter doesn’t really matter, so a semicolon is reasonable. If you omit name entirely, is it really accurate to say noname=yes? Indeed, an ideal renderer would give the street two separate labels running along either side of the line. In this case, name is a stepping stone for data consumers on the way to using the more specific tags.
There are also cases where the authorities on either side apply their name to both sides, such as this road that runs just inches north of the border between Michigan and Ohio (which once fought a war over the border). To this day, Williams County, Ohio, continues to post street signs on its side of the border calling it County Road T, even though the road lies entirely within Hillsdale County, Michigan, which maintains both sides as Territorial Road. They aren’t being petty: deliverers and emergency responders need to be able to find the addresses on either County Road T or Territorial Road.
Or consider the case I brought up in this openstreetmap-carto issue of a street where two authorities have joint authority over both sides of the street. They disagree about the road name, to the point of posting competing signs up and down the street at regular intervals. Should it go without a name in favor of loc_name and reg_name? If there’s this much outcry about less sophisticated renderers showing semicolons in labels, imagine if the labels went away entirely because of an absent name.
I don’t suggest any change to Londonderry/Derry. As you say, it has become a single compound name. Users benefit from knowing why it’s called Stroke City. No one would call it Stroke City if it were routine for a city to have a stroke in its name.
If the name that English speakers should use is in fact “Twmpa”, borrowed from Welsh, then perhaps “Lord Herefords Knob” should be relegated to alt_name:en? If someone needs to know that Twmpa comes from Welsh, they can consult Wiktionary or Wikidata Lexicographical Data or infer that based on name:cy.
A more extreme example is the situation several years ago when World War II–era German names for places in Poland were being tagged as name:de, even though the politically correct tag would’ve been some variation on old_name:de.
Americana doesn’t label hills yet. Depending on stylistic considerations, it may or may not end up showing local-language glosses on natural features.
I’m not sure how this question is in opposition to what Americana is now doing. The point of local-language glosses is to give some sense of what the signs would say, or more generally, what the locals would say in a moderately formal context.