Government funded efforts can be disrupted by the tax software lobby.
The IRS has to program all the rules into their system anyway. If they could simply standardize those rules into a git controlled Yaml file or something better suited, keeping software updated could be made rather easy for open source projects.
The French tax office for example has created a programming language in which the legally binding tax code is defined.
Should be, yes. Will be, no. Tax preparation is a multi-billion dollar industry.
It can start as an open source project and can end up goverment-funded.