I can't help but feel like stuff like this is reacting to noise in the data. Like, if Paradox games didn't exist, the people who form this particular right wing subculture would just be in a different right wing subculture. The primary drivers of people to right wing thought are the same as they've always been, and this is just a highly localized expression of that drive.
It's wild to me that people can play Paradox grand strategy games and come away from it as a right-winger. Especially with Europa Universalis and Victoria, they're Marxist geography simulators which should teach you that fascism costs more than it gains you. Whatever resources you get from colonialism, you'll be fighting rebellions and world wars over bumfuck territories. Whatever economic benefits you get from slavery, the social externalities severely limit you in the long run. Whatever social benefits you get from state religions and oppression, the economic externalities limit you just as much. It's a multi-century struggle session for whatever stupid right-wing belief you think would work for more than a decade.
not blasting the games themselves since as you say they really do try to put in historical context, but do you really find it wild that the games that let you play as nazi germany and win WW2, or play as (insert favorite country with favorite flavor of nationalism here) and colonize more of the world than they originally did IRL, or prevent the fall of (favorite flavor of DEUS VULT nation here) has a huge right-wing playerbase?
they're gonna take fascism/slavery/theocracy makes the game harder and take that as an epic gamer challenge and completely bypass any possible lesson of the game with the same vigor as someone approaching a SL1 playthrough of a souls game 
It's an epic gamer challenge, but one that comes up against being enough of a spreadsheet nerd to learn a game like that. I've had Papal States runs to try to make the Kingdom of Heaven for the novelty of it. It sucks. Everyone hates the church and I play whack-a-mole for centuries while sabotaging my own shitty economy and going to war over minor countries. Playing as the American Confederates means like 30%+ of your population is permanently radical and unable to do skilled labor, your standard-of-living is severely limited, and every country without slavery has a permanent war justification against you. It empowers your landowners who steal all the surplus for themselves. HOI4 Nazis can cheese their way to an early war victory, but it's the worst power bloc in terms of allies and doing fascist things tanks your stability. Colonialism across all the games is only profitable in very limited contexts, but going for those choice territories means perpetual war and overextension while not building up your core. Fascism isn't fun in their games and it punishes you in ways that make it super frustrating to play. Line permanently go down in a game where the entire loop and dopamine source is line go up.
DEUS VULT
Random thought but "god wills it" is just pre- Gen-Z "it is what it is"
A big part of what they talk about here is that the right wingers who play these games make mods that confirm their worldview and let them play out their fantasies.
Got a recommendation for someone who has never played any of these games?
Victoria 3 is the most accessible of them and is also the most intuitive to a socialist. It has a wonderful feedback loop between economic and social improvement, captures a really interesting period of 19th-20th century history, and the modding community is strong.
Europa Universalis V is the most in-depth if you want to get lost in history. It has so much detail and covers a 14th-19th century timespan across the globe. However it's harder to learn than Victoria.
Crusader Kings III is like if The Sims had a complex genetics model and took place in a really detailed 9th-14th century simulator. Its UI is harder to learn than Victoria, but it has the most individual character development. There's also a really fun post-apocalyptic mod called After the End.
Thanks!
I found a YouTube link in your post. Here are links to the same video on alternative frontends that protect your privacy:
Tabletop, DnD, board games, and minecraft. Also Animal Crossing.
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