I don't think "opinionated" has a necessarily negative connotation, at least coming from some fields. For instance, I see it fairly often as a point of pride from the author in software; a statement that the thing does what it's supposed to The Right Way (TM) and that its specific choices provide the kind of focus you describe.
The Right Way is kind of the duality of the problem, what's good for the author may not be good for someone else, but then it's pretty fortunate that we have so much variety in TTRPG material (and in software), for those like a different opinion or would rather build their own thing.