Some films may be crap to you, but liked by others. You are not correct any more than other people are, because it's all just taste. Its incredibly presumptuous that discussion of movies goes anywhere beyond what I like and you like, as if there is some greater truth that exists outside of our perceptions.
As to herd mentality, you are basically writing off anything that is popular, which is not constructive or any sort of specific argument, nor is it proveable in any case. As to non-ST fans, WOK is usually the only film any of them can stand in my experience, and STIV was by far one of the more critically and commercially successfull of the series, which implicates a strong non-fan approval (I would say precisely because it is the least Star Treky all the films). Anyway, it's hard to even divide non-fans and fans in the ST world because usually anyone that likes some of the films is considered a fan, and most people who don't consider themselves a fan in some degree don't like ANY of them, hence the disussion about ranking popularity becomes moot.
The herd argument is stupid and in bad taste though. It's not much an argument as it is unfalisifiable paranoia.