IMO Satisfactory is tailored at a different audience.
Factorio is about efficient solutions and designs. The feel I get from the trailer, Satisfactory is about first person immersion, maybe (hopefully) combat, exploring and adventure. It changes the gameplay drstically, if I can ponder over a design in top down perspective for hours, or if I have to fit something working together, by moving around in FP view with limited oversight and maybe an enemy attack looming. I am also a FPS player and I very much like the prospect of that.
Satisfactory seems to be more in the path of minecraft, space engineers and those games. Satisfactory adds a 3rd dimension to factory building, which is a big plus. On the other hand, as it is a 3D-game and hardware resources are limited, factories will never be as big as in Factorio. Also, IF it is moddable, it is far more complicated to make new assets in 3D, thus the mod variety will never be as large as in factorio. And IMO moddability counts in this genre. I clocked around 1k hours in Factorio and going for the same goal, with the same mechanics gets outright boring after a while. Even if the path is long and the challenge to make the designs more efficient is always there. Last of my thoughts is on action. In Factorio the challenge by the enemy is horribly neglected. In Factorio I plop turrets and walls - or in a more efficient playstyle, I kill every hive in pollution reach - and I don't have to think about the enemy anymore. Maybe Satisfactory does it differently. Hopefully. The ability to use FPS gameplay to create a challenge is a big advantage on Satisfactory's side.
I will monitor Satisfactory closely.
What you can take from it?
1. Before you finish the game hire an RTS expert and ramp up the enemy challenge and the combat gameplay.
2. Finish Factorio and maybe get workign on Factorio 3D
The game of my dreams would have these chracteristics:
1. 3D, real time building and FPS combat
2. In every new game the surroundings, the tech tree (which is not visible in full from the start), the resources, the recepies and the enemies are randomly different. Let's call it the nature is different. So I never know what I will have to build, what I have to fight and what is an efficient way to do so.
3. I have to find out while under constant attack.
4. Still I want a construction planer and blueprints.
Prevailing in this setting would give me a true feeling of accomplishment.
Edit:
A little story:
We were playing multiplayer and advanced to somewhere beyond laser turrets. But the factory was sabotaged by griefers. Power was down and the enemy overran the factory. All players except two left. We grabbed some bullet turrets, ammo and as many of the most expensive items that were safely salvagable. We ran through enemy territory, out of pollution range until we found a suitable spot, cleared it and we built another factory and prevailed. That was the most amazing action and accomplishment I ever had in Factorio. A true adventure with blood and sweat in our eyes (not literally). Building the rocket in this or any other playthrough after that was dwarfed by it.
Edit 2:
I went to youtube and found the Satisfactory Q&A:
https://www.youtube.com/watch?v=W1E6EWrAsII
What I take from it is that Coffee Stain is going for an AAA-title with polished graphics. And that's it. No mods, no base defense (they are makign fun of the idea of turrets) and - I do not beleive it - no procedurally generated maps or resource locations. So I play every game on the same map, with no challenge or diversity at all. Though 3D, FP view and exploring in vehicles is still fun, fuck that. It is like real FPS versus gameplay in comparison to COD Single player campaign with a controller. Oh boy, a cash grab against dull couch potatoes who probably wouldn't even understand how to play Factorio.
What you can take from it?
How to make a cash grab. How to aim at couch potatoes.
Have a look at their campaign or tutorial. Most likely it will make a hughe effort to teach idiots how to play their game.
That is how the world spins. It angers me every time. Wube and Factorio are shining lights in the darkness.
'nuf said.