After I switched to Green MX spacebar, I've made 2-5% less mistakes on my typing games... And it has been pretty consistent..
The MX- Springs "reduce" in resistance over time by as much as 5-7g, so given the "heavy" spacebar + "greater, wear and tear" + stronger thumb/wrist action... It would make sense to use a stronger spring for the space bar..
Also, with an MX Green switch, the space bar feels "less wobbly" than when I had the MX blue. And the Key return to standard position is notably more "robust"