Do I actually have to use the xFi gateway?

Instead of paying $50 for unlimited data I was offered xFi with unlimited data for only $15 (this is before the COVID waivers on data caps). However I already have a high end router and high end mesh network setup, and don't particularly want to reprogram every wifi device in my house (there are dozens) by using the new gateway. I noticed that the data usage coding in my account has been updated to unlimited. Do i actually need to setup the gateway or can I just leave it boxed up? Am i actually going to miss out on anything except the xFi control features (app, etc)?