It's not even really US-centric - it's that too many settings are controlled by one option "locale" and if you want a mixture that isn't represented, you're stuck, even in the USA. Example: ISO standard date 2026-05-14 with 24 hour clock, US digits 1,000,341.24, dollar signs, and English. Most systems won't let you get this, because they have one setting that controls all of it.