I also doubt this will help.
If you go from one place in the map where your factory is, and then go to a place with dense vegetation, the game loses a lot of fps even when you go back to your factory where everything was running with good fps.
The problem at the moment, is the game has not yet been fully optimized to deal with all the graphics and memory leaks.
Early access... that's is what we have.
I bet this will be improved in the future. Also, remember this is made in unreal engine, it is a power hungry engine and is even worse when not fully optimized.
I am sure the devs are on to it, that is why we do not still have the whole map developed. There are many things to come into the game.
I bet next year we will have a blast from Satisfactory.
Give them time.
They will fix it.