As someone who hasn’t owned a television in decades, why would a TV even need a microphone in the first place?
How many other household devices have a microphone whose primary function is orthogonal to recording audio?
Every speaker can be used as a microphone if the circuitry is added to do so.
Of course it is needed in a https://en.wikipedia.org/wiki/Telescreen ...
Some "smart" TVs could do skype in the past, I'm not sure if they needed external headsets of worked with builtin mikes.
1984 purposes.
There are lots of good reasons that are used to paper over the abuse cases.
Microphones in tvs are a useful accessibility feature when they enable voice commands for the user, and allow them to be used as voice assistants.
They also enable tvs with a camera and microphone to be used as video calling or audio calling interfaces. Used well we get star Trek view screens, used poorly we get little brother monitoring.
For those interested, it turns the tv into an interactive terminal for voice and camera powered video games, which are becoming more popular.
Unfortunately advertising and tracking incentives drive the abuse cases to the top and will crush the positive use cases :(