>it's safe to assume there have been some lessons learned since then.

The main lesson learned was that it was ineffective to rely entirely on outsourcing. The government needs top-notch engineering talent in-house. This led to the creation of the United States Digital Service (USDS), a fantastic group of people which did some of the best web design and engineering on the planet.

https://www.usds.gov/

Trump killed them, of course, and the website is now entitled "United States DOGE Service". I hope that, some day, I will no longer be embarrassed to be an American.

afaik https://ndstudio.gov/ (and GSA?) are now the ones responsible for such in-house engineering?