Rich Communications Service (RCS) has received yet another blow, as an interoperability initiative announced in 2019 by the leading US carriers has been closed down. The Cross Carrier Messaging Initiative (CCMI) was set up by AT&T, Verizon, T-Mobile and Sprint as a joint venture to develop an RCS-based messaging service that would be interoperable across all their networks. This was seen as a way to kickstart adoption of RCS, the GSMA-backed technology that was supposed to give operators a way to fight back against WhatsApp and other over-the-top messaging services with an alternative that supported many kinds of rich content. The US agreement was particularly focused on getting business support for a way to enable messaging to their consumers. According…