I am not really familiar with the economic situation of Wikipedia but, if their goal is to be able to keep running for years to come I think it makes a lot of sense to keep asking for donations.

If Wikipedia had no money on hand and were always at the mercy of the organizations and government programs that they receive grants from, that would be a bad situation I think.

You really do need to have some runway, whether you are a commercial business or a non-profit.

Perhaps Wikipedia is asking for too much, but I would really rather see them ask for too much than too little. Wikipedia is a very important project that is doing a great deal of good simply by continuing to exist as a free and open encyclopedia that anyone can contribute to.