In fact, Bitcoin would still be popular and would continue to be so even without a movie about it or Satoshi, because everyone already knows and believes in the stories that have existed throughout its history. As long as the movie doesn't deviate from the story and history, I don't think there's any harm in watching it.
Since the stories that made it popular are often adapted into films, this has become a common practice, and this positive impact can make Bitcoin more widely known, especially to those who are unfamiliar with it, or even unfamiliar with it at all.
The same goes for movies based on true stories that are adapted into films, which can help those who were previously unaware become more aware.