This is a single datapoint, but my hypothesis is that political correctness does indeed account for a measurable (beyond noise) portion of a RT score. Marketing spend probably matters more, and genuinely excellent non-PC films (say, Oppenheimer) can succeed without PC, but PC does contribute.
[0]https://fandomwire.com/theyve-been-barely-advertising-it-unt...
They focus first on their political objectives, their political views, and what political issues they wish to advocate for above all else
This has been an increasing trope in modern film and shows.
"The narrative" is now even a meme... The other coded phrase for a "politically correct" film is "re-imagined for a modern audience"
Recent history has shown us that any narrative can be termed “political” if it helps one side drive a narrative.
Just look at the faux outrage over induction ovens and banning beers. Completely fabricated nonsense used to drive a narrative. This is the true trope.