Comment by jefftk

The important thing isn't how much of a project is "overhead", it's what you get for your donation. A project distributing lollypops might have 5% overhead, but I would still prefer to donate to one that distributed vaccines with 30% overhead.

In this case their program expenses are a mix of incredibly valuable things ("keep wikipedia online") and more borderline things ("redesigning the article editing UI"). When their fundraising talks about the former as if it's what the marginal dollar will be spent on, that's pretty misleading.

(I don't think this marketing is unusually misleading for a non-profit, and likely better than average; the bar for honesty in fundraising is depressingly low.)