The idea that Star Trek fans are more likely to go see a new Trek movie than others seems plausible enough. Almost by definition it must be true. But does that make them less discerning? I don't think most Trek fans had any difficulty recognizing that Nemesis was a poor film.
Even if a ST film had no redeeming qualities at all, I'd still go (on opening night) just to satisfy myself that I'd given it a chance. I was terribly disillusioned by ST V, but watching it (and lampooning the hell out of it) with friends was one of the best nights at the cinema. Shatner tried to give me a very different type of experience, but we went for incredulous hilarity instead. We still got our money's worth.
So, one can be discerning - as in knowing a movie is a bit of a dud - but still actually going to see the movie. When ST V first came out on VHS, I made a point of buying an ex-rental, a few weeks after its release, rather than getting one in pristine shape. I did the same or the DS9 pilot episode, "Emissary", because that series left me rather cold until about "Blood Oath".
As disappointing as ST V, GEN and NEM may have been for me, they each had moments that were well worth seeing, often several times.
I still find it hard to believe so many US fans actively boycotted NEM in its opening weekend. Funnily enough, when NEM came out on DVD, it won its release weekend in the US. So..., presumably, US fans who didn't want to be seen coming out of the cinema still caught up with the movie - in private - as soon as they were able.
