I can't speak too much to the first several points, but noting
- agency micromanagement of contractors
- general red tape
is very fitting and a direct contribution to
- too little competition
I worked with a startup company ~8 years ago that wanted to go after government contracts. According to the owners, everyone they demo'd the product to said it was very clearly superior to what they were currently using.
Unfortunately, the people who would use it are not the people that sign off on paying for it. Those people had checklists of irrelevant requirements, slow response times, almost certainly pressure to select "certain" vendors (i.e. those who threw money into lobbying the right folk). It got to the point where they seriously considered hiring a consulting company whose sole purpose was to help others navigate all the red tape that gets thrown in your way when you try to get government contracts.
In the end, they realized that they were better off pivoting entirely to the private sector instead of doing a half and half approach.
I seem to recall a similar tale with the lead pipe retrofitting in Flint, MI... contractors to do the job were picked not necessarily by speed and capability, but by other qualities. Regardless of how they were chosen, though, the city failed to deliver. Despite the crisis starting in April 2014, residents and activists had to sue the city in 2017 to actually get the work completed, and it still isn't done. Mostly done, but not completely... 8 years later.