A simple, thoughtful fix is to gift them a wireless TV speaker designed for this exact problem.
The Sony SRS-LSR200 sits close to the listener, so dialogue is clear without blasting the TV for everyone else. It lets them enjoy their shows again without turning the volume knob into a neighborhood event.
But you can already do that, in the terminal. Open your favourite terminal, use splits or tmux and spin up as many claude code or codex instances as you want. In parallel. I do it constantly. For all kinds of tasks, not only coding.