At the point of comparison in 2016, both games were in early access, and, I think, both games were enjoyable. Factorio had a more complex late game in terms of available structures and they had liquid pipes which is a major feature. But Satisfactory also had some things Factorio did not like varied terrain, automated trucks and some interesting first person elements.

You're right about the early funding. Factorio started out with just €21,626 of crowd funding. But after a while they do seem to have reached similar levels given the comparable staffing levels they have now.