For what it's worth, Charity Navigator gives them 4 out of 4 stars with a 98.33/100 rating: https://www.charitynavigator.org/ein/200049703
Meanwhile eg the American Cancer Society gets 73/100 and spends more on fundraising than WMF's entire budget, so oncologists can snort blow off hookers in Vegas, but nobody cares.
The whole premise of Wikipedia (or aspiration, at least, and yes, not always fulfilled ...) is that people should have information so they can't be manipulated.
It kind of sucks to see the very organisation hosting the site do the opposite, don't you think?
But the banners I've seen have invariably been about the imminent demise of Wikipedia. Not that they got lots of other side projects they want funded.
Charities seem to do do that sort of thing to raise money, probably because it works and also because the current activities are already funded.
When donations are sought after a disaster the implication is that the money is going to directly help the victims, but the reality is that it will fund other efforts, possibly including helping the victims of a future disaster.