DrDamn as people in the comments have pointed out, if open world games are treated more harshly because of the workload they present - most likely as a sort of unconscious bias say, rather than overt policy - how does that square with EG giving AC:valhalla, which is very much the open world template cliche, a glowing review?
We can and should also consider the ‘different reviewer, different opinion’ idea, but that of itself presents an issue. If a website overtly says “we give reviews of similar games to different people, so there’s no reason to be expect them to be consistent with each other” then that largely devalues the point of a review to the reader, because it completely removes the context by which readers can evaluate that review compared to their previous experiences.
If you have no editorial policy to ensure some level of objective analysis to a standard, then it’s not really ‘a review’, it really is just ‘an opinion’. And the two aren’t actually supposed to be the same, no matter how the people making the subjectivity argument protest.