It's a sign of how popular Genshin Impact has become that Honkai: Star Rail is discussed more like its sequel than the fourth entry in the Honkai series. Along with a complete tonal 180 from the 'Breath of the Wild clone' derison Genshin Impact drew at launch, these constant comparisons can understandably irk some Honkai Impact 3rd players, but it's really tough to separate the two due to how similar they are. Cut out all of the annoying grinding and open world from Genshin, then whack it in a blender with turn-based combat and a squeeze of Honkai lore, et voilà, you've made a Star Rail smoothie. Not exactly a healthy one, when considering your precious gaming time, but healthier than falling off another cliff because your stamina bar depleted again on your third day farming for character materials.
So is that it? Is it just a sci-fi Genshin that cuts out the more time consuming activities? A big part of me wants to say yes. You could put a screenshot of the two side-by-side and it'd be tough to tell them apart, from similar character models and environments, right down to the UI. However, that description feels like it's doing a disservice to Star Rail's delightfully goofy humour, charismatic voice cast, and truly magnificent combat.
It's not just a sci-fi take on the Genshin formula, but you'll certainly have a helpful cheat sheet in understanding how the systems work if you've been playing Genshin Impact for a while. There's not really a similar benefit from having played previous Honkai games as far as I could tell, as Star Rail is set in an alternate universe with different versions of some returning characters. I'm sure it's fun for Impact 3rd fans to see Bronya and Seele reunite again, but I still enjoyed exploring their new story as a relative newcomer to the series.