In my opinion, a film is not dated, but rather reflects an historical perspective that is different from those of the current time in which the film is being viewed. Some people will call that dated, and that is fine, but I do disagree with it as a criticism. And sometimes that difference in perspective either does not exist or is, as they say, timeless.
And as for things like dated effects or styles, that falls under the same category too. It must be taken into account that a film made in the 70s is not going to have the same polished look of effects produced today. And sometimes the film is better for it. These things do not diminish my enjoyment of any particular film, and in fact can sometimes add thoughtful reflection when taking history into consideration.
But I also accept people who think differently than I do, like my entire group of friends who struggle with anything over about 20 years old, have any language other than English, and isn't a film everyone has heard of. But I assume we all have friends like that. I have come to accept the fact that any silent, foreign, or black and white film will probably be watched by myself.
P.S. To directly answer the question posed, if you want to date a movie, go for it, I usually go for girls though.
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