"I don't think there's any evidence whatsoever that the government is capable of making software to either provide a service similar to TurboTax or to correctly pre-calculate your taxes."

Yes and no. When the government wants to get quality software that solves real problems and saves taxpayer money, it manages to do so:

https://en.wikipedia.org/wiki/Dynamic_Analysis_and_Replannin...

"We saw how well that worked with healthcare.gov."

Keep in mind that healthcare.gov was overburdened with moronic, ideologically driven requirements that were still being finalized a week before it was supposed to go live. It was being set up for failure from step one.