Google is doing everything to get Apple to adopt RCS  

He has a whole site about it

Google has long been trying to get Apple to adopt the RCS messaging protocol, the successor to SMS and MMS, without success. Now he’s decided to use public pressure, setting up an entire website for the cause and calling on the public to ” help Apple get the message out.”“. The site clarifies that the blue and green bubbles in the messages that distinguish Apple from Android devices are not the issue, but the problem lies in the blurry videos, the broken group chats, the “read” notifications that do not appear, the lack of sending via Wi-Fi and more. As Google points out, these problems exist because Apple refuses to adopt modern messaging standards in communication between iPhone and Android phones.

In iMessage there are many possibilities for communication between Apple phones, but texts from Android devices are converted to SMS and MMS, which means using 30-year-old technology.