Probably.

I realized elsewhere my main pont wasn't so much about donating, but rather that by converting people to a more rational way of thinking would lead them to convince themselves to donate as an optimal strategy. Then again, if it really is most rational to improve the rationality of others, then that is what they would do rather than donating. (One also has to work enough to eat, but constraints are different for everyone so I am ignoring that)

There is an additional issue in that we are not totally rational, and also value other things than the reduction of human suffering.