you can not decide whether bitcoin is a good project or not just based on its paper. you have to actually check the project to see if that "idea" was implemented correctly or not. for example there are some altcoins that had good ideas but failed horribly in implementation step so their whole project is now considered a failure.
We cannot judge a project by its whitepaper alone. A whitepaper is indeed important to know the overall details of the project. As what most called it, it is indeed the "roadmap" of a project. Some whitepapers are excellently written, researched, explained, and presented but on the implementation stage, still failed. And there is also some project's whitepaper that is the opposite--or maybe just created on an average level but still able to present or explain everything about their project well--and yet proven to be legit or successful.