This is making mountains out of mole hills though: these types of problems can be solved without abolishing tax-deductible accounts. For example, one could twe

This is making mountains out of mole hills though: these types of problems can be solved without abolishing tax-deductible accounts. For example, one could tweak the deadline for contributions to those accounts to be say March 1, make the financial institutions report to the IRS by March 15th, send everyone their estimate on April 1st and have a deadline of April 15th to confirm or adjust their tax filing. Most of the big things that involve deductions are already tied to a financial institution that already report to the IRS.