One of the things FedGov has always struggled with is how to enact "checks and balances" that don't ultimately become /rigid requirements/. There are a lot of complicating issues in government acquisition, and political maneuvering can completely crater otherwise great ideas (this is true at companies, too, but I would argue is less prevalent).
It's worth noting that the National Defense Authorization Act of 2018 actually has a section devoted to piloting an Agile development & acquisition process for defense software systems to address a slew of issues, including the one we are discussing, here.
All of Subtitle H in the NDAA-2018 is relevant for people with an interest in how the FedGov handles software, but Section 873 specifically lays out the Agile Development initiative:
We're a place where coders share, stay up-to-date and grow their careers.
We strive for transparency and don't collect excess data.