I would have nothing against overrated games if it weren't for two things
Limited development resources and statements made in ignorance.
The issue with games like Call of Duty (To pull out the old argument) is not that they are bad, in fact I think CoD and most of it's competitors are well made games, but their popularity is so massive that it's began to inform the design of other games, games that have no business with multiplayer or even being a part of the shooter genre itself.
CoD clones might not be bad games per say, but everyone that is made represents a more interesting game idea being rejected.
Even still, if I though it was what everybody really wanted I wouldn't begrudge these game simply for being overrated, but this brings to the second reason; a lot of people who do things like claim CoD is their favorite game have played a very small amount of video games.
This is simply due to CoD's massive popularity; even if you generally do not play video games, you have probably played Modern Warfare at least once, and there are many people who basically play CoD and nothing else.
When these people say they love CoD, I find it hard to believe they mean the same thing I do when I say I love Knights of the Old Republic II.
KOTOR II is one of the only works of art, one of the only pieces of fiction, that has ever changed the way I thought or believed about something; when I say I love it I don't mean it's fun, I don't mean I play it constantly, turn my brain off and pretend nothing else exists, I mean it changed me as human being, I mean it and the few other stories like it are what enabled me to discover what I want to do with my life. It is not an exaggeration to say that KOTOR II is part of the reason I am who I am today.
So when the only thing I hear from people who say CoD is the best game ever is that it's fun, that they kick ass at sniping or they like the new guns, that it's basically engaging, I'm sorry, but to me that's not the same thing.
I don't believe that anybody could honestly want every game released to be under pressure to be more like CoD, but when you blow $60 on a set of new guns and a campaign that doesn't last the afternoon every time a new one is released, and play almost nothing else, that's exactly what happens.
When I say games like CoD or Halo are overrated, I don't mean that too many people like them, I mean that nobody likes them enough, nobody really loves them.
In conclusion, it might be inaccurate to refer to CoD as overrated, it might be better to describe it as overly exposed, the fact that the three games that are basically the public persona for video games are Mario, Zelda and CoD should evidence that.
So I would not advise anyone to stop plying Call of Duty, I have no interest in telling people what to like, instead I would offer financial advise; don't spend $60 dollars on 7 hours of new content. You can save money if instead of buying Call of the Halo Wars 67: Modern Reachfare you just keep playing the old one. While your at it, if you really decide you like video games, why not try playing one from a genre you're not accustomed to? You might find a game you actually love, that has a genuine impact on your life, something you really cherish.