XB7 and WiFi 6

I'm considering changing out my own modem router for Xfinity's XB7 router.  Does the XB7 router support the 802.11/ax WiFi protocol WiFi6 ?   And if so, can I assume that WiFi 6 is available from Comcast for my area because they tried to get me to start renting the XB7 router? 

I just want to make sure it is worth it to change from my own router to renting the XB7 from Comcast.