It doesn't say "immediate post game opinions" but this
I will be posting polls like this after big wins an big losses to gauge how everyone is feeling about various aspects of the team.
is pretty close. Basically saying, right after the game we are posting the poll to gauge how people are feeling in the aftermath of either a good win or a bad loss.
it also says poll will be closed before next game, indicating that the feedback sought from these polls is designed to be fairly recent and tied to the most recent game.
PS that's not the last poll. Dak's approval in this poll you linked is in the high 80's
the most recent poll was a total reversal of that #, with his disapproval in the high 80's. Just for accuracy's sake.