I think you have a point, but context is important. And I say this as someone who has been repeatedly accused in this forum to make abundant use of "weasel words" just to qualify the boundary between fact and opinion. As a result I don't do it as often anymore, especially when the context of the subject itself already serves as a good indicator that whatever follows will be opinion.

Still, I have to admit that I do believe it to be factual that extremely successful people did not have to work on making themselves pleasant or conformant to the same degree as normal people. I explained the reasoning for this in the sister comment, but the upshot is that I indeed see this as a fact that probably could be supported by biographical evidence.