Factorio is very much like programming on a good team, automation, expansion, refactoring, tooling used to solve your problems.
Satisfactory is cool, but at no point do you get the "ok so I built this entire factory and now I can just replicate it modularly" - no, just place every, single, block, by, hand.
To me factorio is a rethinking of the RTS game, satisfactory is like a really nice minecraft mod.
Now, granted, they might change their minds -- but it's hard to imagine how blueprints would work. Factorio is played on a 2D plane, with few obstacles in general and none that can't be removed; Satisfactory is played in a 3D world with immutable obstacles.
The game is tuned towards not needing blueprints. You don't need large quantities of anything, just a small amount of every item -- the complexity scales up, but the scale itself kinda doesn't. Yes, some players will attempt to turn the entire output of the map into turbo-motors, producing exactly the right amount of every ingredient, and will build their factory in the sky to avoid dealing with the terrain--
And yes, blueprints could be useful in this specific case. But that's not most players.
I think its possible, and I might switch over my opinion if such a thing existed - it'd still be hard to optimize it to build worlds of "factorio level" complexity.
Factorio is (kind of) infinitely scalable. There is no max map size, and the game engine's performance is so incredibly good that it can support absolutely insanely massive factories. You can go as big as you can imagine, and the game will keep up.
It's also ridiculously stable, in the ~thousand hours I've played I've never had a crash or a game breaking bug.
Meanwhile satisfactory puts you on a fixed-size map and will slow down to a crawl once you build too much. This limits a lot of the things you can do in the game.
The simple answer is scale. The recipes in satisfactory and factorio are pretty similar in complexity, but the production chains in factorio are quite a bit larger. Also a lot of complexity comes in with scaling production up in factorio, since you largely have to scale horizontally, but in satisfactory, most of the scaling is vertical. Later, you can do more horizontal scaling, but even into the mid-game, you're pretty constrained by the amount of resource locations you have access to.
I play both. Satisfactory has more game in the sense of doing things besides designing a factory. Factorio is close to pure factory building, whereas it's like 70% in saisfactory.
Satisfactory has more elements of a traditional open-world action game (that just happens to borrow factorio's factory system).
Satisfactory is cool, but at no point do you get the "ok so I built this entire factory and now I can just replicate it modularly" - no, just place every, single, block, by, hand.
To me factorio is a rethinking of the RTS game, satisfactory is like a really nice minecraft mod.