[sho_hn]

As treasurer of a similar FOSS org, this is the correct take.

An important responsibility of the people running a FOSS community's backing non-profit is to keep the org safe and stable, as the community relies on it for vital services and legal representation. A risk like that is unacceptable, even more than in commercial business.

[echelon]

Could the foundation take the money and sit on it in bonds or some other safe instrument? Call it an "endowment"?

$1.5M at 4% is nice.

But I suppose the "proposal" means these funds come with a distribution plan attached?

[sho_hn]

Typically in grant work you submit a complete proposal with milestones and roles defined, and receive payout over time to cover the costs in the plan, or some part of them. It's earmarked money.

In more established non-profit areas there's usually also quite some compliance overhead and audits to be passed, so this can be someone's fulltime job on the org side. FOSS backing orgs are typically smaller and less experienced, so donors have so far found ways to make things easier for them and give more leeway.