Probably because he has other things he cares about more. I won't deny that his original statement was rude, but we have to be able to point out flaws in things without feeling obligated to try to fix them. Otherwise, we won't be able to give most kinds of constructive criticism, which is bad for everyone.
Of course, if we won't help with problem in an open source project, we shouldn't feel entitled to a fix either.
Of course, if we won't help with problem in an open source project, we shouldn't feel entitled to a fix either.