interesting response which only makes sense as we have more information than when I started the thread.

it’s called communication:”dear passenger, we apologise but your seat has been found to be inoperable for your flight. As we expect to be very busy we have selected an alternative seat for you. We appreciate this is not ideal and if you paid for a specific seat, please refer to x for details on how to get your refund.

we trust you will enjoy your flight.”

hardly rocket science and in the grand scheme of things a minor inconvenience. But it does not take much to turn something into a potential positive or at least reduce the annoyance.

your response does little except attempt to embarrass the passenger that the issue is irrelevant.