We have a user matrix with user access levels defined as to who can view what dashboard in Tableau and what level of data. Can we have mechanism in Tableau to create individual extracts depending on these users as the users will be viewing it in Tableau Reader or try to handle this in SQL server(which is our backend).
Any leads would be really helpful.
Please read the Tableau Reader EULA - Legal | Tableau Software
You cannot use Tableau Reader to open and consume files created in an automated fashion.
It sounds like what you need to use is a combination of Row Level Security and Tableau Desktop / Tableau Server.