The other major recruiting problem is marijuana prohibition. Government has a lot of problems retaining high-skill IT people because a huge number of computer-touchers smoke. iirc FBI has commented on their inability to hire good technical staff because they can't find anyone who doesn't smoke.
And it's not just a question of willingness to smoke or not going forward, for most public-trust positions you're going to have to abstain for at least a year before even applying.
What are you willing to give up for a job offer that you might not even get? For computer-touchers with lots of other options, that answer is "not much". And federal jobs are basically low-paying, highly-competitive, and high-bureaucracy, when you could be making bank and having a reasonably satisfying work experience in the private sector.
And thus you filter out a huge number of the exact people you're trying to hire - young techies who are familiar with modern IT and development practices.