I'm curious as to why you think people are misunderstanding that one.
So, I wrote a really long reply to this, then realized that it's really a tangent to this anyway and I shouldn't ramble on, because the real point is that I feel like the tone of this comic is in contradiction with the point of that other comic. The short of it: I think there's a clear distinction between mocking someone for not knowing something, and mocking someone for being too lazy, stubborn, or narrow-minded to know something, and that comic only addressed the former, while it is occasionally cited in response to people being hostile toward the latter. I may be overstating how widely it is applied to the latter category, I don't know. If you disagree, that's fine, I can't be asked to look for examples. :)
Anyway, back on topic, that probably wasn't the best example to use in arguing that everyone is hypocritical. It's as inevitable as change is, because the two are directly related. Because change is constant, it is inevitable that people are going to grow up with social norms that are in conflict with social norms that develop later in their lives. Like, I grew up in a world where three-legged mutants living underground at the sites of nuclear accidents knew their place and stayed underground where we barely even knew they were there. Am I ready to live in a world 50 years from now where they're living above ground and demanding the right to vote and stuff? I don't know if I can ever be ready for that. But I'll try.
That's all anyone can hope for: That when confronted with accusations of hypocrisy, they are open-minded and honest enough to consider the arguments, assess their own behavior and decide if they do in fact need to change*. But that's not always easy. In fact, it's one of the hardest things you could ever do, changing as an adult behaviors you have learned and constantly reinforced since you were a child. In some cases, it is relatively unimportant - my 83-year-old grandmother never bothering to learn how to register an email address and in general being terrified of the Internet didn't harm her or anyone else, in my view. But her view discomfort in the presence of black people is less forgivable. On the other hand, an American who is 50 years old today, while not part of the Internet Generation, would most likely be having a significant negative impact on their life in some way if they never learned how to use email. I'm in my late 20s, in 20-30 years I am surely going to be confronted with many changes in lifestyle that I kind of by definition cannot even fathom right now. Hell, I'm confronted with those kind of decisions already now. How I deal with those changes I guess in some ways is what defines me. Ditto for everyone else.
I guess if you assume certain things about this comic, then the tone might be appropriate. For instance, if this is a conversation that these two women have had many times, then perhaps the tone is justified because the character is frustrated. But taking it in isolation, I think it's a assholeish argument.
* - To clarify, I should of course acknowledge that this is never, ever allowed to happen on the Internet.
Also curious as to why you think either of these characters is speaking for RM.
Again, I guess it really doesn't matter. I don't know the dude and it's not really relevant. But whether he agrees with the argument or not, he's knowingly putting it out there in a context that tries to make it seem like a very compelling one in his fairly widely read comic. So I don't know how it couldn't be speaking for him in some way. Unless it's an anthropological experiment on his part.