It’s perfectly appropriate to complain about not getting the experience you were sold and paid for. That doesn’t mean it’s okay to be abusive to staff, but I really do not see any unhinged posts across this or any other forum I participate in. Princess really botched this launch, screwing over their passengers on the Feb 8 & Feb 18 sailings, and not providing more equitable adjustments to their current sailing for the lack of open infrastructure.
People are right to expect to get what they paid for and to expect for Princess (or any cruise line) to make it right when they fail to deliver. That doesn’t mean those people are never happy, want Princess to fail, or have unrealistic or unreasonable expectations.