Joker is about economic inequality leading to a worsening society that's decaying. An abused, but now evil and homicidal clown seeks revenge and inspires others. We clearly have economic inequality, underinvestment in citizens and infrastructure, and a decaying society, and people are increasingly turning to revenge because the traditional levers of power are largely corrupt and inaccessible to people d/t mass bribery and lobbying.
Luigi is clearly a bit of a Joker figure, but he didn't really turn himself intentionally into a symbol or try to rally people like in the movie. I personally don't consider anything regarding the Kirk stuff to be a great parallel with that since he was a pretty low level propagandist for the Trump administration and mostly focused on youth outreach and nothing about the apparent motivations has to do with economic inequality but seems to be more about trans / feminist culture war stuff.
Times of extreme and unsustainable economic inequality have frequently led to violence. French Revolution, etc. People have warned about this for years. Instead of taking the warnings seriously about economic inequality at a level that rivals ancient Egypt, they want to pretend it isn't there so they are afraid of movies that reflect basic sociology in a fictional setting. No one should fear a fictional movie. They fear that it is reflecting societal trends they want to ignore.
We'll be fully at Joker level when a killer shows up like that and he manages to escape, and stream online about it with some kind of manifesto spreading online. The way to prevent going down this Joker dystopian route is to increase taxation on the mega wealthy and corporations, root out legalized bribery, lobbying, Citizens United allowing elections to be bought, and invest more in society and everyday people. Elon Musk openly told everyone he feels he personally bought Trump the election. This is terminal decay stuff for society and it's on both sides. Violent extremists are more of a late end-stage symptom, not a cause.
