Left handers are also less confused when facing right handers because there being more righties, everything is made for righties and everything is done from the perspective of righties. So from birth on the lefty is faced with a righty world and learns to deal with it, making most lefties become ambidextrous either in part or in everything when they must. That may change since left handed products are now easily available.
I think the researchers are thinking too much in an eithor/or way and haven’t really thought about the lefty’s forced ambidextrousness [or the righty’s dependence on their right hand from a life of ease in never being required to learn to use the left hand] being the real advantage against right handers in baseball, etc.
My parents and grandparents had a lot of kids and about half were left handed when writing or dining out of habit but could use the right hand albeit more clumsily for these tasks. Of those, all could easily use their right or left hands for shooting, fly fishing, driving nails or using tools, playing baseball, etc. with no clumsiness, while the same could not be said for the right handed kids. Right handed siblings were strictly right handed, no ambidextrousness at all.
Scissors used to be made strictly for righties. Now days, they make left handed scissors. Simple solution for lefties who haven’t learned to cut right handed is to turn right handed scissors upside down. Put your fingers in the thumb hole and your thumb in the finger hole. Don’t know why that works unless it is the pressure that’s put on the blades.