Opacity is important to DARPA’s outlier success so the industry standard flashy announcements about what you’re going to do are off the table.
Minimizing short term glory is awkward for getting philanthropic money because Most people give money to philanthropy to make themselves look and feel good and Charities raise money on a yearly or sub-yearly basis. If there are no flashy announcements for people to point to or read about they might pull funding. This constraint might suggest that you could invert the problem and make the opacity part of the appeal of donating: if you give us money you get to peek under the hood.
It means that relationships are especially important because you can’t drive inbounds due to PR.