This article[1] has more details. Sen. Wyden[2] has been pushing for more funding to IRS to develop its free file program, but Turbotax has been successful via their lobbying of Republican politicians and some Democratic politicians in preventing it from happening.
1. https://www.propublica.org/article/inside-turbotax-20-year-f... 2. https://www.nytimes.com/2021/07/19/opinion/intuit-turbotax-f...