I think it's the Woke Left's mantra of "Everything is political" has been leaking into the mainstream rapidly over the past several years.
You sort of saw it during GamerGate and SJW's defending pretentious walking simulators and other woke indie hipster fare, and then it migrated onto defending shit like Fembusters, Black Panther, and The Last Jedi and conversely demonizing things like Joker.
It doesn't help that so many Millennial leftists treat Marxism and postmodernism like a religion thanks to college indoctrination, and Marxism is all about making everything political.
Entertainment is seen as bourgeoisie in Marxism, and the only purpose it can serve in a Marxist or communist society is as a form of cultural propaganda.
Postmodernism also lends itself well to making everything hyper-political, even if the thing in question is otherwise apolitical.
Look at hobbies and "nerd culture" in the 2010's and how they went from mocked in the 80's and 90's to being seen as trivial but otherwise tolerated in the 2000's, to somehow being a focal point of aggressive social political debate in the 2010's.
Again, the dominance of left-wing postmodernism in academia and its impact on the Millennial generation is why autistic internet slapfights like Gamergate became these huge cultural debates and why so many SJW's still blame Gamergate for damn near everything from Trump's election and Brexit to the invention of AstroTurf and the cancellation of Firefly.
Half a decade after it became dead and irrelevant, so many SJW's talk about Gamergate the same way that TERF's talk about patriarchy and /pol/ talks about the Jews.
TL;DR-Blame the corrupt universities and the fundamentally broken Millennials/Early Zoomers who fell for their bullshit