My thoughts - I would love to see Data back, he's one of my favourite characters, died in a contender for worst trek movie ever, and was even given plot dialogue to be resurrected in that selfsame movie.
To each one's own. I liked Nemesis
on the whole; I felt that Data was wasted as a character in the movies once they walked back the emotion chip and abandoned all the story possibilities that came with it, so I don't mind that his story ended; and I feel the movie went to great lengths to explain why B-4 couldn't
realistically be expected to turn into Data 2.0, and that final bit at the end was just offering hope that maybe he could grow beyond his limited beginnings after all and serve as a legacy left by Data.
Then again, the very nature of Data as an AI means that finding a way to reconstitute his consciousness could potentially be handled more plausibly than your typical resurrection, as long as it were done in some other way than the "B-4 turns into Data" route, which is not only unlikely in the context of what the film established, but is deeply undesirable because it would mean murdering another individual so that Data could live. (Not to mention that it's too predictable -- there are surely more interesting ways it could be done.)