Who is assuming the worst? I'm not the one who's claiming that the guy deliberately left women off the list. I'm assuming he sat down, thought of a bunch of movies and made a list. It probably never crossed his mind that there were no women.
And, honestly, I have no idea why it even matters. Had it not been pointed out to me, I'd have never even thought about the gender (am I allowed to say that word?) of the directors. It seems irrelevant to the subject matter.
Isn't it worse if it wasn't deliberate? Then, either he unconsciously marginalizes women. Or his first list was right, and now its patronizing to pad the list with lesser movies because equality.
Everybody is biased. The average person is blissfully unaware. Better people are aware and attempt to compensate. The worst of us are aware and embrace it.
We all do things like this. It says nothing about us, other than that we're human. Our character is shown by how we deal with it, not by whether we do it at all.
Considering that Lee's reaction was to essentially say, "Oops, thanks for pointing this out, here's some more," I'd say he's doing OK. But somehow everybody's losing their mind over it.
Why assume the worst?