I'll play devil's advocate here and assume for a moment that all of the code was, in fact, uploaded to GitHub/BitBucket/etc today. How would open source improve

I'll play devil's advocate here and assume for a moment that all of the code was, in fact, uploaded to GitHub/BitBucket/etc today. How would open source improve it? Remember that successful open source projects do not operate by simply throwing code over the metaphorical wall. Meaning, you're not just asking for the code, you're asking to be a part of a community that needs management. Bug reports, pull requests, contributor agreements - these cost time and manpower/money to curate, which neither CGI nor the Federal government are going to supply overnight. Ultimately, given the rapid deadlines they're supposedly facing, I'd argue that, at this point, they're distractions to the actual development team.