Try the pulse audio settngs first as you will see Auto Echo Cancellation is pulse audio module as its the Google WebRTC that is Auto Echo Cancellation that is why its sets your source and sink to AEC.
Give it a go first before turning anything off.
PS Andlo is giving a radio skill a go and might also be of interest.
Not really sure what ‘The rpi hardware just doesn’t have what it takes for true echo cancellation.’ means to be honest as device aec isn’t hardware based ?!?