Man, I've been fired by for-profit companies and felt lucky to get four weeks severance. It's upsetting that people working for a non-profit are getting 1.5x their salary, but I guess this is kind of what we get for believing that a non-profit is going to act better than an evil corporation.
While I think Wikipedia is highly suspect given its ample reserves and continued begging, it should not be upsetting for you. It should bring you joy that someone got treated well.
However, Wikipedia is a non-profit, and their messaging in their donation drives always sort of implied that they really needed these donations. Since Wikipedia is a non-profit, I do have higher aspirations of how they're going to allocate their funds: chiefly in making the highest quality freely-available knowledge resource even better.
If they had given these people a three month paid severance, I would not criticize them at all. That's very generous and there is value in making sure employees are treated well. 1.5x your annual salary though? I'm sorry, but there's "generous" and then there's "shady".