Not quite the case, thankfully. I'm left handed and greatly benefit from this style of keyboard layout. I tend to notice that I'm more finger-agile with my left hand, which helps with quickly chained left hand shortcuts (C-z/x/c/v/a/s/tab, M-x, anything with shift or windows) and WASD movement.
As for the right, as some other commenters have noted it really isn't that bad to use your non-dominant hand with a mouse. Most of the movement precision comes from the wrist and elbow, rather than finer finger control.
As for the right, as some other commenters have noted it really isn't that bad to use your non-dominant hand with a mouse. Most of the movement precision comes from the wrist and elbow, rather than finer finger control.