Or regulations in China:
* https://www.miit.gov.cn/gzcy/yjzj/art/2023/art_2d5a7969581b4...
* https://old.reddit.com/r/UniversalProfile/comments/153rrwl/c...
* https://9to5google.com/2024/02/16/iphone-rcs-china/
* https://www.macrumors.com/2024/02/20/apple-rcs-message-compl...