The standards issue is only relevant to E2EE. It has no bearing on the usability issues here. The E2EE issues should be fixed soon according to Apple. I'd bet a good amount of money the usability issues will remain.
It used to be black text on green: https://mobiforge.com/files/iphone-sms-1.jpg
The white-on-acid-green color combination would not make it through any accessibility review. It's literally impossible for a lot of color-impaired people to see, and objectively unpleasant otherwise.
Apple gets plenty of complaints about it. Just look at the Apple forums. Their literal advice to fix it is "make your friends buy an iPhone".
