Jessie, it’s a fresh pie with a fresh install, but I found out it’s not the AIO installer, Libcec is broken and there’s a ticket - (my progress: HomeAssistant AIO HDMI CEC error (clean install))
in particular, this issue should be tracked for those wanting to keep up to date with cec:
https://github.com/Pulse-Eight/libcec/issues/362#issuecomment-317258888