Why not just let everyone use their preferred method for authentication and not forcing a particular doing-it-the-right-way on people? Also, how many accounts

Why not just let everyone use their preferred method for authentication and not forcing a particular doing-it-the-right-way on people? Also, how many accounts and passwords people tend to have which are pets rather than cattle? Bank and email can cause major headaches and probably everyone has 1-2 more accounts which they value and would cause significant setbacks if compromised. Passwords are plenty fine.