Art from Symbaroum by Free League
The greatest strength that tabletop roleplaying has always held over videogames and even more traditional boardgames is its sheer flexibility. If you want to take your fantasy game and send it into space for a few sessions, you don’t need to worry about buying the latest DLC or even customising your playmats and cardboard standees. Instead, you just throw out a few lines about seeing the stars stretching away to infinity and BAM! Things are all sci-fi’d up.
Almost uniquely among gaming, this malleability explicitly stretches to the rules themselves. Virtually every RPG rulebook out there has some little note saying something to the effect of “hey, if there’s anything about this game you don’t like, make it up yourselves!”, and almost every single gaming group I know has taken advantage of this to tinker with the ruleset of their games here and there.