I don't think anyone's really saying "don't dare post", more just that if you weren't reading BEFORE they killed Janeway, didn't read the book where they killed her, and aren't reading any of the aftermath of the decision, it's pretty absurd to have much of an opinion on the subject, as you don't have any basis to actually react to the decision, as you don't have much of (or any of) the information or context.
Same goes with talking about the sales, how you'll boycott, and how the sales numbers could be improved. You weren't buying before, so a boycott is just continuing current behavior, and the sales are doing quite well, so didn't take the downturn you're claiming, or offering ways out of.
Honestly, not sure how we're even keeping this thread going, when only half the group has done their homework for the discussion. (Almost exactly ) like trying to have a bookclub discussion with someone who has strong opinions on a book they didn't read. Half the group are discussing what happened, reactions, aftermath, etc, the other half just throwing unsupported opinions or 'facts' against the wall and calling the other half sexist for not agreeing...