I think it has to do with familiarity. It just felt unnatural to me as the other lefty bolts have the safety on the left.
Using your logic, why do NONE of the right handed bolts have the safety on the LEFT side?
Admittedly, small numbers. However, over the years, there have been a few variants of right hand rifles with safety on left side. Apparently some Peruvian Mausers came thus equipped. And some FN Mausers. Also NECG offers three position swing safety conversions for RH Mausers with a LH safety for those so inclined. Commercially, Right Handers preferring a Left Hand safety are probably fewer than true Left Handers. Hence the dearth of LH safeties on RH arms.
