They didn’t because it’s not their problem. Other platforms’ users have that problem; Apple users have iMessage.

You buy a Windows phone, you buy a blackberry, you buy a flip phone, you’re using carrier messaging, or whatever app you can run on those platforms.

You buy an Android and suddenly you feel entitled to demand Apple to go to bat for you on carrier messaging? That’s a very entitled hot take.

Apple users have iMessage… amongst other third party chat apps that works fine across different platforms. Apple doesn’t have any obligations to go to bat for other platforms on carrier messaging that they already support.