I don't think it's actually that important that every language deals with them the exact same way. I interpret that to mean they all translate the APIs as liter

I don't think it's actually that important that every language deals with them the exact same way. I interpret that to mean they all translate the APIs as literally as possible between them, using the same method names, same types of arguments, etc. Different languages all have their own quirks and patterns and it's also useful that the library be idiomatic within the language. Most of the problems I have seen in dealing with time, across various languages, arise from allowing types to be way too ambiguous. A lot of code uses interchangeably things like "UTC -0700" and "America/Los_Angeles" which are actually very different (one incorporates daylight savings and one doesn't). The important fix is that languages start using reasonable abstractions and are stricter about requiring explicit conversions between types rather than trying to implicitly guess an interpretation. The first library I've seen get this right was Joda in Java, and it later got included into the standard library for Java. It's been copied other languages, and I've used it on the frontend a bit as JSJoda, but the literal translation makes it a bit awkward in JS and I found it was hard to get other JS developers to prefer it over the more popular moment or date-fns. Temporal looks great, it actually seems to borrow heavily from Joda but doesn't literally copy all of the names or methods so hopefully it will be the best of both worlds.