Of course the film should be able to show that it is high quality entertainment, but the millions of people who will see the film have widely varying expectations and determinations of what is or isn't "high quality" entertainment. And again, you're speaking as if a film's RT score is the measure by which audiences judge a film, or an accurate measure of a franchise's potential to reach audiences.
Going by your logic, Jurassic World's 71% RT score should have limited its audience, or will limit its audience in the future -- something we know isn't true. Or that since Avengers: AOU had a 75% RT score, there will now be a significant drop-off in box office for future Avengers/Marvel films.
Alternatively, we have a film like The Revanent with an 82% RT score (or "low 80s" as you'd call it) that is nominated for a slew of Oscars and has been a pretty big box office success for a film of its kind.
Also, when you focus so much on the actual score numbers of 75% vs 82% vs 92%, you lose sight of what the scores themselves actually mean. While MOS's score of 56% shows that reviews were clearly mixed, it still shows that there were more positive reviews than reviews that skewed negative (168 vs 128). When you get into the 70s like with Jurassic World, that shows that there were an even greater majority of postive reviews over negative ones (198 vs 80). The Revanent having a score in the low 80s doesn't look amazing, but it still had 207 positive reviews over 45 negative reviews which is really great.
Of course, the ideal scenario would be for BvS to have a super high score like TDK or Star Wars. But it's important to realize that saying that a score must be nearly unanimously praised by critics in order for it to impact audiences positively is certainly asking for a lot, and certainly not always true.