I think you're just perceiving a difference in how it's expressed by each of them, e.g. one reply is that ESR has a very clear goal of increasing the quality of software. Which for me is the big difference between "Free" and "Open" software.
Oh, he is certainly ego-driven, but not in the same way as Jobs was, for example. RMS does not put his person before everyone else, but he lives rather through his principles and tries to convince everyone why it makes sense to follow them. And he has a very solid rationale he has developed through the years, making him very articulated.
No, he's driven by a very clear goal to prevent non-free software, even if that means preventing free software that might, potentially, in the future, be used by someone, somewhere, to create non-free software.
And I think there is a certain amount of ego in there that gets in the way of good judgement on means, in that he tends to take actions which will naturally result in the free software he protects from being involved in producing non-free software losing mindshare to either non-free software or free software not wrapped around with his preferred restrictions, which is contradictory to his purpose -- since it means that not only does software that isn't crippled in features to prevent its utility in contributing non-free software wins, but that that software is also itself either non-free software, or non-copyleft free software that can more readily directly contribute to non-free software as well as being used by people who might build non-free software through use of the features of the software.