When considering Google pushing for RCS, keep in mind Google has sabotaged MMS in Android for 10+ years due to the convenient Stagefreight bug. MMS being a practical and once widely used (for ringtones and such) content distribution channel with carrier billing out of Google's reach and ever increasing lust for sensor data that can be used for ad targeting. Think sending literature, reports, music for pennies (with greedy telcos kept in check in a regulated market).