I do not think he's trying to twist anyone's arm

I agree he's not explicitly trying to twist anyone's arm; he doesn't say "do this". But he's making clear that he has a strong opinion. See further comments below.

Have you watched his videos?

I have now--I had only really briefly skimmed them before. I'll comment on them in reverse order to the order you linked to them, because, ironically, if you'd only given the link to the second one (Media for Thinking the Unthinkable), I'd be more inclined to revise my impression; but the first one (Inventing on Principle) contains some elements that the second one doesn't.

I agree with his general point in the Media video, although I would state it slightly differently: our representations of systems constrain how we think about them. For any given representation of a system, there will be some thoughts about that system that are "unthinkable" using that representation. So it's good if we can find multiple representations of systems, particularly important ones. (Feynman once said that any theoretical physicist who is any good knows several theoretical representations for exactly the same physics.)

I also agree with his point about representations constraining how thoughts can be communicated; his example of a well-written paper still being incomprehensible because the authors had no other way of talking about their findings than dense mathematical jargon is a good one, and his reworking of the paper is a good illustration of how changing representations can greatly help in understanding an idea.

He also makes a key admission at the end of the Media video, which I did not expect after reading the article that started this thread. He admits he doesn't know what "the new medium" will be. In the article, he says we don't know what is going to be important in 100 years, but he appears to be saying we can still, right now, know what tools to build to help our children to see it. At the end of the video, he seems to be saying that's not the case--he doesn't know what tools to build, but he's dedicated to searching for them. Fair enough--if that were the only video I had seen, I'd say you were right, he's not proselytizing, he's just informing.

But in the Inventing video, the stance he takes is quite different. Much of the underlying material is the same; but there are two key points that aren't there in the Media video. First, he says he views creators being constrained by their tools as a moral wrong. At that point (about halfway through the video), he says he's not trying to make everyone believe that--he's only trying to show that you can believe that. But at the end of the talk, he explicitly contrasts his view--find a principle, find something you think is morally wrong, and fix it--with taking the path that is "laid out for you" by parents, teachers, corporations, whatever; he says "you can choose to sleepwalk through your life, but you don't have to." That's proselytizing. And as far as I can tell, his audience in that talk is at least partly students, so proselytizing makes me even more uneasy than it would in a talk for a general audience.

So bottom line, I agree his overall position is more complex than I made it sound in my original post upthread; but I still think he's trying to influence people as I was using the term, and it still makes me uneasy.