The long fight to make Apple's iMessage compatible with all devices has raged with little to show for it. But Google (de facto leader of the charge) and other mobile operators are now leveraging the European Union's Digital Market Act (DMA), according to the Financial Times. The law, which goes into effect in 2024, requires that "gatekeepers" not favor their own systems or limit third parties from interoperating within them. Gatekeepers are any company that meets specific financial and usage qualifications, including Google's parent company Alphabet, Apple, Samsung and others.
It's quite literally well documented that Apple doesn't want to support RCS because it pressures people to get iPhones. SMS is an ancient garbage protocol, what Google is trying to do is get Apple to support SMSs 21st century replacement and RCS support will fix literally every issue iPhone users have texting Android users. Broken group chats, trash quality videos, ultra compressed images, no reactions or stickers, threaded chats etc etc
Google wants Apple to use Google’s proprietary extension of RCS, which runs on Google’s own servers as is precisely as open as iMessage. Effectively nobody uses the industry-standard version of it.