The script seems to be written mostly from the perspective of Jim Balsillie, a businessman that was co-CEO of Blackberry, while engineers take a backseat. This follows the general tendency in film to glorify businessmen, treating the people who actually conceptualize, design and implement the products (i.e., do the core work that is societally useful) as mere sidekicks.
The general timeline is right and many of the major events in the history of Blackberry are there, but none are described in enough detail for viewers to appreciate the engineering successes that led to Blackberry rising to global prominence, nor the business mismanagement that tanked it.
The engineering details that made it in are often confused or misleading (e.g., Blackberry did not invent push messaging, and their prototype wasn't pulled from thin air overnight). It gives the impression most of the source material came from interviews with non-technical people, or else "Great Man" personality drama was the only material the filmmakers understood well enough to put in a script.
The film has confusingly mixed messaging. It perpetuates the notion that engineers are tinkering children that get nothing done without big daddy managers pushing them to work long hours and "just make it work", damn the technical details! Yet it repeatedly also tries to show the businessmen as hustlers that use bluster and hand waving to cover up their general uselessness and technical incompetence, as well as the resulting harmful decisions they make that ultimately resulted in the downfall of Blackberry. Perhaps the writers wanted to portray Balsillie as a clever shark, but based on his actions in the film alone you would think he was largely a egomaniacal leech that the meek engineers could not figure out how to get rid of. Indeed it is unclear why the engineers brought him on to begin with - they probably would have been better off without him and the other businessmen he brought on.