[joeyo]

  > For example, we don’t call it “Constantinople” any more

Not to detract from the rest of your point, but "Istanbul" actually comes from a Greek nickname meaning "to the city", and didn't even become the official name until 1930.

[jan_Inkepa]

Curious, about this, I got sucked into a rabbithole of reading about this background of this etymology. Thanks for the nerdsnipe! :)

"THE ETYMOLOGY OF İSTANBUL: MAKING OPTIMAL USE OF THE EVIDENCE"

https://ruj.uj.edu.pl/xmlui/bitstream/handle/item/15924/stac...

(It disputes the details of the traditional 'to the city' etymology, but in the end proposes deriving from something else with very similar meaning, "στην­ Πόλι" (something maybe like 'sten­ Poli' but there are details of historical pronunciation in the article I didn't read closely) rather than "εἰς­ τὴν ­Πόλιν" [is timˈbolin].)

[orestarod]

Without reading the article, if it is between "στην­ Πόλι" and "εἰς­ τὴν ­Πόλιν", I can tell you, as a Greek, it is exactly the same phrase. Poli/Polin (Πόλη/Πόλιν) are interchangeable, the same word with a different suffix but with both the same purpose, and "στην" is just "εις την" stiched together.

[coldtea]

Similar to the difference between "is not" and "ain't".