The IRS already has this software. They are literally the best placed people in the world to make this software.
How do you think they check taxes for 300,000,000 people + businesses? And their software is already pre-populated with data from employers, banks, brokerages, and all the other places that automatically file data with the IRS.
I 100% agree that the IRS should handle the majority of simple taxes. I just don't think it's reasonable to expect them to find all the possible deductions or suggest complex strategies for you. They could offer common suggestions & try to remind you of common deductions though.