The app is the full implementation of Rich Communication Services (RCS) and it has 3-4 dozen Java Packages alike business info, chat seeing, business payments, file transfer, RCS service.contact, etc. Carrier Services app also includes IMS registration information for each carrier like WiFi calling, visual voicemail, etc. It integrates various features into the android operating system with the support of Google. The app also brings support for the enhancement of the Messages app.
Google makes it impossible to disable all their services but to root your phone and can install a custom ROM it may possible to disable carrier services.