Not sure why you need a "smoking gun" when it's clear that pretty much all of the more negative reviews on the game had one thing in common - they brought political commentary in to the fray.
Some even went as far as to spell it out to us that they were docking points due to those reasons:
The hotly anticipated PS5 exclusive action game Stellar Blade is finally here, but how does it stack up against its peers?
www.thesixthaxis.com
There's a reason I said go back and revisit the review thread for that game, there are a ton of examples like that coming from Western journalists.