Hello Team,
My newly purchased 75-Inch Class QNED 4K LED QNED85T series TV with webOS 24 has a setup box and soundbar connected via HDMI. It automatically returns to HDMI input when I move between home and any app (like YouTube, Prime, etc.). It appears to automatically detect and switch to the HDMI input always. The soundbar attached to the HDMI was disconnected if I turned off Simplink (HDMI-CEC). There doesn't seem to be a way to disable auto sensing option. It appears that LG TVs lack a function or problem.
I have a Hisense TV with the same setup, and it functions perfectly. I have no trouble switching between apps and controlling devices connected via HDMI.