HDMI-CEC(BraviaSync in Sony products) can be convenient but the receiver will receive commands from TVs and devices rather than give them. So, turning the receiver on will not result in the TV turning on, though turning the TV on will result in the receiver turning on shortly afterward.
When using eARC for TV apps or directly connected devices, make sure Digital Audio Output and Passthrough are set to Auto. You also need at least a Premium Certified cable that supports ethernet for eARC. But Ultra Certified cables are recommended for systems supporting HDMI 2.1.
If the receiver is connected to a wifi network, using the Marantz app for system adjustment and source selection may prove preferable to using the TV and remote controller. Selecting the HEOS input will switch to the HEOS app automatically and music streaming services, network media servers and USB devices connected to the receiver can be selected there.