In Europe, I have a pre-filled tax report. Of course, it includes only my employee's income and all the banks interest & dividends and deductions they can automatically get (wrt known family situation, loan interest, etc.).

For the rest, it is still up to me to declare additional incomes (e.g. rental properties) or deductions (e.g. donations). It does simplify though the process, especially for "W-2" employees.