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
Well I would not say that you should trust the white paper 100% because sometimes this is the only good thing in a project but the Telegram group and other platforms is where you can spot the signs that the project is a scam.