My parents got a new smart TV; if you don't give it wifi access it will nag repeatedly about it. Very annoying, and it only takes one time for it to go "Yay! I'll store these forever now."
(It will also wheedle you to re-enable the AI features and telemetry if you turn those off. Which you do like eight levels of confusingly and scarily named submenus.)
The best course of action here seems to return the TV. Any TV that cannot be permanently switched to HDMI input without nags is unfit for purpose and should be rejected.