It's more tied to which 19th century prescriptivist happened to have more influence on your side of the Atlantic. Before them, English orthography wasn't even expected to be consistent. Switching orthography en masse through particular prescriptions being adopted by schools in actuality changed the spoken language very little. The new tendency to ignore those spelling rules has also changed the spoken language very little.

Moving to consistent spellings obscured the origins of English words maybe as often as it illuminated them.