How long you been in this fandom? Or any fandom? People are going to call people on hypocrisy. In short: Bring the "A" game. Got an opinion? Great. Start citing how "X" is worse that "Y" cause "Y" is a superior product, you better be willing to back it up and then brace to get it torn down and torched.
If someone is posting their opinion on some important political issue like universal health care or gay marriage I would agree with you. I do not agree with you when it comes to frivolous things such as films. I was talking to a Star Trek fan at work a few weeks ago and he mentioned that Deep Space Nine was the worst Star Trek series without backing up his opinion. Should I have aggressively interrogated him and forced him to compare everything he didn't like to the other series? Should I then have "torn down and torched" his argument if his responses didn't satisfy me? Of course not, so why should we behave any differently on these forums?
Eventually this is what always happens. The last resort when someone doesn't like a piece of entertainment is dissecting that opinion down to the tiniest level. It's an attempt of turning an opinion into something objective, which is a fallacy in itself.
Nitpicks are a symptom, not the cause, guys. When you see a movie, you either like the overall package or you dislike it.
So that whole "you must hold everything to the same standard" is absolute bullshit. Because there is no standard. The standard is at best "I liked it, so I overlook some flaws here and there" and "I disliked it, so I see flaws everywhere."
So stop that objectively scrutinizing bullshit. If that's your last straw in an argument to "defend" a film, just stop it.