his desire to prioritize the "freedom" of systems over those systems actually doing anything useful is totally unreasonable
It's more like a desire to prioritize the freedoms of software users over those of software distributors. He's not against software doing "useful" things, except where the usefulness lies in somehow exploiting the software user.
Software freedom is so much less importsant than other forms of freedom (freedom from slavery, freedom of speech, freedom of association, etc) in the real world that I can't take his writing seriously.
Of course, freedom from slavery is clearly much less important than freedom from murder. I mean if you are enslaved you can regain your freedom, but if you're dead you're dead. Should we then legalise slavery once again so we can concentrate on the big picture? I'm sure there are lots of other pesky laws that we could get rid of while we're at it. Always assuming your logic of prioritising freedoms holds water, obviously.
The only people who can stand to listen to him are those who forgive those traits because they already agree with what he says.
Counter example right here. I don't agree with everything rms says. I don't believe that proprietary software is necessarily a bad thing, and I take particular issue with him on the "GNU/Linux" thing. In this instance, however, I think he's got it about right.
You can't expect to grow a movement that way, even if your movement has a purpose that makes sense.
So you're saying that popularity is more important than principle? Presumably rms should abandon his notion of the Four Freedoms and adopt something less controversial, like maybe "oxygen is good" in the expectation of seeing the GNU movement expand dramatically. Personally I think it's his refusal to compromise his principles that has gained him so many followers.