The fact that this isn't in the conversation has always surprised me. Both Regan and Obama supported it. The Republicans did that whole "taxes on a postcard" skit, but we don't even need a postcard. We're talking about TurboTax, well how many of you also log in and all the information is already there? I don't see why we can't replace the 1040 with return free filing, or at least the 1040Ez
Grover Norquist has had Republicans sign "the Pledge" opposing tax increase since 1986. Reportedly, he also wants filing taxes to be painful so you hate the government and he opposes these measures.
In 2005, California had a pilot program called ReadyReturn where they mailed you prefilled forms. It was popular. TurboTax lobbied against it and it died.