It is important to know that for any project hoping to convince investors into putting their money into the project, they are going to be focused on making the project as appealing as possible which means that the project's whitepaper will surely be good so I believe you should look beyond the projects whitepaper to decide if a project is legit or not.
Always make through research of a project's team, road map and token metrics to decide which projects to invest in
Whitepaper is their project testament that a investors should look into it to verify if the team has doing base on their whitepaper. This could also attract investors if they found it very interesting. Sometimes whitepaper is not realistic and far from the actual outcome of the project in which investors should be careful not just rely on whitepaper.