It's a non profit so it can receive donations, but the developer is a LLC that's run for profit. It's a similar story in almost all software companies that market themselves as non-profit foundations (Mozilla too btw)
The effect is the same as it is for "regular" non-profits: there are no shareholders (other than the non-profit), and so no incentives to maximise profits.
(Of course employees and board members can still receive handsome compensation, but the same holds true for regular non-profits.)
There are some things non-profits are not allowed to do. But, owning a for-profit isn't one of them, and the for-profit is allowed to do those things. So hence this is a common strategy.
Example: Suppose I bulk buy T-shirts printed with my cool logo for $15 each and I sell them to consumers for $50 each. That's a for-profit activity, if Walmart was allowed to have a "non-profit" arm which did this I'm sure they would, the tax saving would be considerable.
That's decidedly not what "nonprofit" means. A nonprofit can absolutely fundraise like that, and pay the employees above market salaries, or they can use the funds for other things, they just can't return them to shareholders (of which there aren't any), or the board.
https://en.m.wikipedia.org/wiki/Signal_Foundation#Signal_Mes...